Searched hist:50 (Results 376 - 400 of 671) sorted by relevance
/gem5/src/arch/arm/kvm/ | ||
H A D | gic.hh | diff 13014:a4f71c3dc602 Thu Aug 30 09:50:00 EDT 2018 Ciro Santilli <ciro.santilli@arm.com> dev-arm: rename Pl390 to GicV2 The Pl390 model has evolved and acquired a lot of the features from GICv2, which means that the name is no longer appropriate. Rename it to GICv2 since this is more representative of the supported features. GICv2 is backwards compatible with the older Pl390, so we decided to simply rename the class to represent both GICv2 and older interfaces such as the instead of creating a new separate one. Change-Id: I1c05fba8b3cb5841c66480e9f05b8c873eba3229 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/12492 Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> |
/gem5/src/arch/power/insts/ | ||
H A D | branch.hh | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC. |
/gem5/src/arch/power/isa/formats/ | ||
H A D | mem.isa | diff 7045:e21fe6a62b1c Tue Mar 23 11:50:00 EDT 2010 Steve Reinhardt <steve.reinhardt@amd.com> cpu: fix exec tracing memory corruption bug Accessing traceData (to call setAddress() and/or setData()) after initiating a timing translation was causing crashes, since a failed translation could delete the traceData object before returning. It turns out that there was never a need to access traceData after initiating the translation, as the traced data was always available earlier; this ordering was merely historical. Furthermore, traceData->setAddress() and traceData->setData() were being called both from the CPU model and the ISA definition, often redundantly. This patch standardizes all setAddress and setData calls for memory instructions to be in the CPU models and not in the ISA definition. It also moves those calls above the translation calls to eliminate the crashes. |
H A D | branch.isa | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC. |
/gem5/src/dev/alpha/ | ||
H A D | backdoor.cc | diff 7823:dac01f14f20f Sat Jan 08 00:50:00 EST 2011 Steve Reinhardt <steve.reinhardt@amd.com> Replace curTick global variable with accessor functions. This step makes it easy to replace the accessor functions (which still access a global variable) with ones that access per-thread curTick values. |
/gem5/src/dev/arm/ | ||
H A D | kmi.cc | diff 12772:362544959c40 Mon Jun 04 12:50:00 EDT 2018 Nikos Nikoleris <nikos.nikoleris@arm.com> dev-arm: Fix the address range for some I/O devices Previously, many devices were incorrecty configured to respond to an address range of size 0xfff. This changes fixes this and sets it to 0x1000. Change-Id: I4b027a27adf60ceae4859e287d7f34443b398752 Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-on: https://gem5-review.googlesource.com/11116 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> |
H A D | rv_ctrl.cc | diff 7823:dac01f14f20f Sat Jan 08 00:50:00 EST 2011 Steve Reinhardt <steve.reinhardt@amd.com> Replace curTick global variable with accessor functions. This step makes it easy to replace the accessor functions (which still access a global variable) with ones that access per-thread curTick values. |
H A D | gic_v3_its.cc | diff 14168:2a96e30b9400 Wed Aug 14 12:50:00 EDT 2019 Giacomo Travaglini <giacomo.travaglini@arm.com> dev-arm: Add GITS_PIDR2 register to the ITS memory map The GITS Peripheral Identification Register #2 bits assignments are the same as those for GICD_PIDR2. Change-Id: I235008a383e08dd557d899cb3aa18202ef943f8b Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20254 Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> Tested-by: kokoro <noreply+kokoro@google.com> |
/gem5/configs/common/ | ||
H A D | Benchmarks.py | diff 11949:db6d68484756 Mon Apr 03 18:50:00 EDT 2017 Gabe Black <gabeblack@google.com> config: Add a default system disk image for SPARC FS. When the change below removed the hard coded disk name for the SPARC FS configuration, it broke the regression which had not specified a disk name. This change adds a default disk name so that the regression will continue to work like it used to, but preserving the effect of this other change. commit 86a25bbcee88f6e69299867b6264885d738f636e Author: Jakub Jermar <jakub@jermar.eu> Date: Tue Jul 19 09:52:46 2016 -0500 config: Allow SPARC FS image to be specified on the command line Change-Id: Ieb317b2bf573a4f2fc435d34cccd1f246c28d84c Reviewed-on: https://gem5-review.googlesource.com/2645 Maintainer: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> |
/gem5/src/arch/arm/linux/ | ||
H A D | linux.hh | diff 13536:77e19417e723 Wed Jan 09 09:50:00 EST 2019 Andreas Sandberg <andreas.sandberg@arm.com> sim-se: Refactor clone to avoid most ifdefs Some parts of clone are architecture dependent. In some cases, we are able to use architecture-specific helper functions or register aliases. However, there is still some architecture-specific that is protected by ifdefs in the common clone implementation. Move these architecture-specific bits to the architecture-specific OS class instead to avoid these ifdefs and make the code a bit more readable. Change-Id: Ia0903d738d0ba890863bddfa77e3b717db7f45de Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Cc: Giacomo Travaglini <giacomo.travaglini@arm.com> Cc: Javier Setoain <javier.setoain@arm.com> Cc: Brandon Potter <Brandon.Potter@amd.com> Reviewed-on: https://gem5-review.googlesource.com/c/15435 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Brandon Potter <Brandon.Potter@amd.com> |
/gem5/src/arch/power/isa/ | ||
H A D | operands.isa | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC. |
/gem5/src/arch/sparc/ | ||
H A D | isa.cc | diff 13583:f7482392b097 Thu Oct 18 20:50:00 EDT 2018 Gabe Black <gabeblack@google.com> sparc: Get rid of some register type definitions. These are IntReg, FloatReg, FloatRegBits, and MiscReg. These have been supplanted by the global types RegVal and FloatRegVal. Change-Id: I956abfc7b439b083403e1a0d01e0bb35020bde44 Reviewed-on: https://gem5-review.googlesource.com/c/13627 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> |
H A D | registers.hh | diff 13583:f7482392b097 Thu Oct 18 20:50:00 EDT 2018 Gabe Black <gabeblack@google.com> sparc: Get rid of some register type definitions. These are IntReg, FloatReg, FloatRegBits, and MiscReg. These have been supplanted by the global types RegVal and FloatRegVal. Change-Id: I956abfc7b439b083403e1a0d01e0bb35020bde44 Reviewed-on: https://gem5-review.googlesource.com/c/13627 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> |
/gem5/src/arch/x86/ | ||
H A D | decoder.hh | diff 11165:d90aec9435bd Fri Oct 09 15:50:00 EDT 2015 Rekai Gonzalez Alberquilla <Rekai.GonzalezAlberquilla@arm.com> isa: Add parameter to pick different decoder inside ISA The decoder is responsible for splitting instructions in micro operations (uops). Given that different micro architectures may split operations differently, this patch allows to specify which micro architecture each isa implements, so different cores in the system can split instructions differently, also decoupling uop splitting (microArch) from ISA (Arch). This is done making the decodification calls templates that receive a type 'DecoderFlavour' that maps the name of the operation to the class that implements it. This way there is only one selection point (converting the command line enum to the appropriate DecodeFeatures object). In addition, there is no explicit code replication: template instantiation hides that, and the compiler should be able to resolve a number of things at compile-time. |
/gem5/src/arch/x86/linux/ | ||
H A D | linux.hh | diff 13536:77e19417e723 Wed Jan 09 09:50:00 EST 2019 Andreas Sandberg <andreas.sandberg@arm.com> sim-se: Refactor clone to avoid most ifdefs Some parts of clone are architecture dependent. In some cases, we are able to use architecture-specific helper functions or register aliases. However, there is still some architecture-specific that is protected by ifdefs in the common clone implementation. Move these architecture-specific bits to the architecture-specific OS class instead to avoid these ifdefs and make the code a bit more readable. Change-Id: Ia0903d738d0ba890863bddfa77e3b717db7f45de Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Cc: Giacomo Travaglini <giacomo.travaglini@arm.com> Cc: Javier Setoain <javier.setoain@arm.com> Cc: Brandon Potter <Brandon.Potter@amd.com> Reviewed-on: https://gem5-review.googlesource.com/c/15435 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Brandon Potter <Brandon.Potter@amd.com> |
/gem5/src/sim/ | ||
H A D | init.hh | diff 11548:91f58918a76a Tue Jun 28 03:50:00 EDT 2016 Andreas Hansson <andreas.hansson@arm.com> scons: Track swig packages when loading embedded swig code This patch changes how the embedded swig code is loaded to ensure that gem5 works with swig 3.0.9. For Python 2.7 and above, swig 3.0.9 now relies on importlib, and actually looks in the appropriate packages, even for the wrapped C code. However, the swig wrapper does not explicitly place the module in the right package (it just calls Py_InitModule), and we have to take explicit action to ensure that the swig code can be loaded. This patch adds the information to the generated wrappers and the appropriate calls to set the context as part of the swig initialisation. Previous versions of swig used to fall back on looking in the global namespace for the wrappers (and still do for Python 2.6), but technically things should not work without the functionality in this patch. |
/gem5/src/cpu/pred/ | ||
H A D | bpred_unit.hh | diff 10244:d2deb51a4abf Mon Jun 30 13:50:00 EDT 2014 Anthony Gutierrez <atgutier@umich.edu> cpu: implement a bi-mode branch predictor |
H A D | tournament.hh | 6226:f1076450ab2b Fri Jun 05 00:50:00 EDT 2009 Nathan Binkert <nate@binkert.org> move: put predictor includes and cc files into the same place |
/gem5/src/dev/x86/ | ||
H A D | SouthBridge.py | diff 9162:019047ead23b Tue Aug 21 05:50:00 EDT 2012 Andreas Hansson <andreas.hansson@arm.com> Device: Remove overloaded pio_latency parameter This patch removes the overloading of the parameter, which seems both redundant, and possibly incorrect. The PciConfigAll now also uses a Param.Latency rather than a Param.Tick. For backwards compatibility it still sets the pio_latency to 1 tick. All the comments have also been updated to not state that it is in simticks when it is not necessarily the case. |
H A D | intdev.cc | diff 8855:74490e94da0c Fri Feb 24 11:50:00 EST 2012 Andreas Hansson <andreas.hansson@arm.com> MEM: Prepare mport for master/slave split This patch simplifies the mport in preparation for a split into a master and slave role for the message ports. In particular, sendMessageAtomic was only used in a single location and similarly so sendMessageTiming. The affected interrupt device is updated accordingly. |
/gem5/src/arch/x86/isa/ | ||
H A D | operands.isa | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC. diff 5429:52dbcf7f7328 Thu Jun 12 00:50:00 EDT 2008 Gabe Black <gblack@eecs.umich.edu> X86: Keep handy values like the operating mode in one register. diff 5428:5a27fea50fee Thu Jun 12 00:50:00 EDT 2008 Gabe Black <gblack@eecs.umich.edu> X86: Change what the microop chks does. Instead of computing the segment descriptor address, this now checks if a selector value/descriptor are legal for a particular purpose. |
/gem5/tests/long/fs/10.linux-boot/ref/arm/linux/realview-o3/ | ||
H A D | stats.txt | diff 11957:90bb43dfc028 Wed Mar 29 21:50:00 EDT 2017 Gabe Black <gabeblack@google.com> stats: Update ARM FS stats. The change below changed the behavior of interrupts on ARM and changed the stats for the 10.linux-boot regression. commit 746e2f3c27ad83c36b7bc3b8bd3c92004fcf995b Author: Sudhanshu Jha <sudhanshu.jha@arm.com> Date: Mon Feb 27 10:29:56 2017 +0000 arm, kmi: Clear interrupts in KMI devices Change-Id: Ie1cfc26777f6ed2d3fd4340175941fda1fdb5b6a Reviewed-on: https://gem5-review.googlesource.com/2653 Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> diff 10242:cb4e86c17767 Sun Jun 22 17:33:00 EDT 2014 Steve Reinhardt <steve.reinhardt@amd.com> stats: update for O3 changes Mostly small differences in total ticks, but O3 stall causes shifted significantly. 30.eon does speed up by ~6% on Alpha and ARM, and 50.vortex by 4.5% on ARM. At the other extreme, X86 70.twolf is 0.8% slower. diff 9348:44d31345e360 Fri Nov 02 12:50:00 EDT 2012 Ali Saidi <Ali.Saidi@ARM.com> update stats for preceeding changes |
/gem5/src/arch/sparc/isa/ | ||
H A D | operands.isa | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC. diff 3418:50e5c0cb3186 Wed Oct 25 17:58:00 EDT 2006 Gabe Black <gblack@eecs.umich.edu> Fixed the priv instruction format. src/arch/sparc/isa/formats/priv.isa: Fix the priv format so that it uses isa_parser operands rather than accessing the registers directly in checkCode. Also, the expressions needed to be negated. src/arch/sparc/isa/operands.isa: Added an Hpstate operand, and adjusted the numbering. diff 2954:6839b9e49575 Sat Jul 22 15:50:00 EDT 2006 Gabe Black <gblack@eecs.umich.edu> Fixed subtract with carry, and started some work with floating point. src/arch/sparc/isa/decoder.isa: fixed subc, subccc, added decoding for impdep1 to fit with ua2005, and started work on floating point. src/arch/sparc/isa/operands.isa: Added in floating point operands, and changed the numbering of operands. src/arch/sparc/regfile.hh: Fixed some memory errors related to floating point. |
/gem5/tests/ | ||
H A D | SConscript | diff 11542:ecd058e3dcbe Mon Jun 20 09:50:00 EDT 2016 Andreas Sandberg <andreas.sandberg@arm.com> tests: Split test results into running and verification The test base class already assumes that test cases consists of a run stage and a verification stage. Reflect this in the results class to make it possible to detect cases where a run was successful, but didn't verify. Change-Id: I31ef393e496671221c5408aca41649cd8dda74ca Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Curtis Dunham <curtis.dunham@arm.com> diff 8492:1ad244a20877 Mon Aug 08 11:50:00 EDT 2011 Nilay Vaish<nilay@cs.wisc.edu> BuildEnv: Eliminate RUBY as build environment variable This patch replaces RUBY with PROTOCOL in all the SConscript files as the environment variable that decides whether or not certain components of the simulator are compiled. diff 2953:10e7700b27f6 Sat Jul 22 15:50:00 EDT 2006 Kevin Lim <ktlim@umich.edu> Last minute check in. Very few functional changes other than some minor config updates. Also include some recently generated stats. SConstruct: Make test CPUs option non-sticky. configs/common/FSConfig.py: Be sure to set the memory mode. configs/test/fs.py: Wrong string. tests/SConscript: Only test valid CPUs that have been compiled in. tests/test1/ref/alpha/atomic/config.ini: tests/test1/ref/alpha/atomic/config.out: tests/test1/ref/alpha/atomic/m5stats.txt: tests/test1/ref/alpha/atomic/stdout: tests/test1/ref/alpha/detailed/config.ini: tests/test1/ref/alpha/detailed/config.out: tests/test1/ref/alpha/detailed/m5stats.txt: tests/test1/ref/alpha/detailed/stdout: tests/test1/ref/alpha/timing/config.ini: tests/test1/ref/alpha/timing/config.out: tests/test1/ref/alpha/timing/m5stats.txt: tests/test1/ref/alpha/timing/stdout: Update output. |
/gem5/src/cpu/testers/traffic_gen/ | ||
H A D | traffic_gen.cc | diff 10392:0100f00a229e Sat Sep 20 17:17:00 EDT 2014 Wendy Elsasser <wendy.elsasser@arm.com> cpu: Update DRAM traffic gen Add new DRAM_ROTATE mode to traffic generator. This mode will generate DRAM traffic that rotates across banks per rank, command types, and ranks per channel The looping order is illustrated below: for (ranks per channel) for (command types) for (banks per rank) // Generate DRAM Command Series This patch also adds the read percentage as an input argument to the DRAM sweep script. If the simulated read percentage is 0 or 100, the middle for loop does not generate additional commands. This loop is used only when the read percentage is set to 50, in which case the middle loop will toggle between read and write commands. Modified sweep.py script, which generates DRAM traffic. Added input arguments and support for new DRAM_ROTATE mode. The script now has input arguments for: 1) Read percentage 2) Number of ranks 3) Address mapping 4) Traffic generator mode (DRAM or DRAM_ROTATE) The default values are: 100% reads, 1 rank, RoRaBaCoCh address mapping, and DRAM traffic gen mode For the DRAM traffic mode, added multi-rank support. diff 10138:0e40c53fe85c Sun Mar 23 11:11:00 EDT 2014 Neha Agarwal <neha.agarwal@arm.com> cpu: DRAM Traffic Generator This patch enables a new 'DRAM' mode to the existing traffic generator, catered to generate specific requests to DRAM based on required hit length (stride size) and bank utilization. It is an add on to the Random mode. The basic idea is to control how many successive packets target the same page, and how many banks are being used in parallel. This gives a two-dimensional space that stresses different aspects of the DRAM timing. The configuration file needed to use this patch has to be changed as follow: (reference to Random Mode, LPDDR3 memory type) 'STATE 0 10000000000 RANDOM 50 0 134217728 64 3004 5002 0' -> 'STATE 0 10000000000 DRAM 50 0 134217728 32 3004 5002 0 96 1024 8 6 1' The last 4 parameters to be added are: <stride size (bytes), page size(bytes), number of banks available in DRAM, number of banks to be utilized, address mapping scheme> The address mapping information is used to get the stride address stream of the specified size and to know where to find the bank bits. The configuration file has a parameter where '0'-> RoCoRaBaCh, '1'-> RoRaBaCoCh/RoRaBaChCo address-mapping schemes. Note that the generator currently assumes a single channel and a single rank. This is to avoid overwhelming the traffic generator with information about the memory organisation. diff 10138:0e40c53fe85c Sun Mar 23 11:11:00 EDT 2014 Neha Agarwal <neha.agarwal@arm.com> cpu: DRAM Traffic Generator This patch enables a new 'DRAM' mode to the existing traffic generator, catered to generate specific requests to DRAM based on required hit length (stride size) and bank utilization. It is an add on to the Random mode. The basic idea is to control how many successive packets target the same page, and how many banks are being used in parallel. This gives a two-dimensional space that stresses different aspects of the DRAM timing. The configuration file needed to use this patch has to be changed as follow: (reference to Random Mode, LPDDR3 memory type) 'STATE 0 10000000000 RANDOM 50 0 134217728 64 3004 5002 0' -> 'STATE 0 10000000000 DRAM 50 0 134217728 32 3004 5002 0 96 1024 8 6 1' The last 4 parameters to be added are: <stride size (bytes), page size(bytes), number of banks available in DRAM, number of banks to be utilized, address mapping scheme> The address mapping information is used to get the stride address stream of the specified size and to know where to find the bank bits. The configuration file has a parameter where '0'-> RoCoRaBaCh, '1'-> RoRaBaCoCh/RoRaBaChCo address-mapping schemes. Note that the generator currently assumes a single channel and a single rank. This is to avoid overwhelming the traffic generator with information about the memory organisation. |
Completed in 177 milliseconds