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baremetal: move aarch64 el.c into dump_regs.c

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Also start disassembling registers nicely dump_regs so we can have a
single executable to handle all register queries.
This commit is contained in:
Ciro Santilli 六四事件 法轮功
2019-05-27 00:00:01 +00:00
parent 3527c8df5b
commit 8eb312c58d
5 changed files with 47 additions and 60 deletions
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70
README.adoc
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@@ -13376,14 +13376,14 @@ ARM exception levels are analogous to x86 <<ring0,rings>>.
Print the EL at the beginning of a baremetal simulation:
....
./run --arch arm --baremetal baremetal/arch/arm/el.c
./run --arch aarch64 --baremetal baremetal/arch/aarch64/el.c
./run --arch arm --baremetal baremetal/arch/arm/dump_regs.c
./run --arch aarch64 --baremetal baremetal/arch/aarch64/dump_regs.c
....
Sources:
* link:baremetal/arch/arm/el.c[]
* link:baremetal/arch/aarch64/el.c[]
* link:baremetal/arch/arm/dump_regs.c[]
* link:baremetal/arch/aarch64/dump_regs.c[]
The instructions that find the ARM EL are explained at: https://stackoverflow.com/questions/31787617/what-is-the-current-execution-mode-exception-level-etc
@@ -13392,53 +13392,53 @@ The lower ELs are not mandated by the architecture, and can be controlled throug
In QEMU, you can configure the lowest EL as explained at https://stackoverflow.com/questions/42824706/qemu-system-aarch64-entering-el1-when-emulating-a53-power-up
....
./run --arch arm --baremetal baremetal/arch/arm/el.c
./run --arch arm --baremetal baremetal/arch/arm/el.c -- -machine virtualization=on
./run --arch arm --baremetal baremetal/arch/arm/el.c -- -machine secure=on
./run --arch aarch64 --baremetal baremetal/arch/aarch64/el.c
./run --arch aarch64 --baremetal baremetal/arch/aarch64/el.c -- -machine virtualization=on
./run --arch aarch64 --baremetal baremetal/arch/aarch64/el.c -- -machine secure=on
./run --arch arm --baremetal baremetal/arch/arm/dump_regs.c | grep CPSR.M
./run --arch arm --baremetal baremetal/arch/arm/dump_regs.c -- -machine virtualization=on | grep CPSR.M
./run --arch arm --baremetal baremetal/arch/arm/dump_regs.c -- -machine secure=on | grep CPSR.M
./run --arch aarch64 --baremetal baremetal/arch/aarch64/dump_regs.c | grep CurrentEL.EL
./run --arch aarch64 --baremetal baremetal/arch/aarch64/dump_regs.c -- -machine virtualization=on | grep CurrentEL.EL
./run --arch aarch64 --baremetal baremetal/arch/aarch64/dump_regs.c -- -machine secure=on | grep CurrentEL.EL
....
outputs respectively:
....
19
19
19
1
2
3
CPSR.M 0x3
CPSR.M 0x3
CPSR.M 0x3
CurrentEL.EL 0x1
CurrentEL.EL 0x2
CurrentEL.EL 0x3
....
TODO: why is `arm` stuck at `19` which equals Supervisor mode?
TODO: why is arm `CPSR.M` stuck at `0x3` which equals Supervisor mode?
In gem5, you can configure the lowest EL with:
....
./run --arch arm --baremetal baremeta/arch/arm/el.c --emulator gem5
cat "$(./getvar --arch arm --emulator gem5 gem5_guest_terminal_file)"
./run --arch arm --baremetal baremetal/arch/arm/el.c --emulator gem5 -- --param 'system.have_virtualization = True'
cat "$(./getvar --arch arm --emulator gem5 gem5_guest_terminal_file)"
./run --arch arm --baremetal baremetal/arch/arm/el.c --emulator gem5 -- --param 'system.have_security = True'
cat "$(./getvar --arch arm --emulator gem5 gem5_guest_terminal_file)"
./run --arch aarch64 --baremetal baremetal/arch/aarch64/el.c --emulator gem5
cat "$(./getvar --arch aarch64 --emulator gem5 gem5_guest_terminal_file)"
./run --arch aarch64 --baremetal baremetal/arch/aarch64/el.c --emulator gem5 -- --param 'system.have_virtualization = True'
cat "$(./getvar --arch aarch64 --emulator gem5 gem5_guest_terminal_file)"
./run --arch aarch64 --baremetal baremetal/arch/aarch64/el.c --emulator gem5 -- --param 'system.have_security = True'
cat "$(./getvar --arch aarch64 --emulator gem5 gem5_guest_terminal_file)"
./run --arch arm --baremetal baremetal/arch/arm/dump_regs.c --emulator gem5
grep CPSR.M "$(./getvar --arch arm --emulator gem5 gem5_guest_terminal_file)"
./run --arch arm --baremetal baremetal/arch/arm/dump_regs.c --emulator gem5 -- --param 'system.have_virtualization = True'
grep CPSR.M "$(./getvar --arch arm --emulator gem5 gem5_guest_terminal_file)"
./run --arch arm --baremetal baremetal/arch/arm/dump_regs.c --emulator gem5 -- --param 'system.have_security = True'
grep CPSR.M "$(./getvar --arch arm --emulator gem5 gem5_guest_terminal_file)"
./run --arch aarch64 --baremetal baremetal/arch/aarch64/dump_regs.c --emulator gem5
grep CurrentEL.EL "$(./getvar --arch aarch64 --emulator gem5 gem5_guest_terminal_file)"
./run --arch aarch64 --baremetal baremetal/arch/aarch64/dump_regs.c --emulator gem5 -- --param 'system.have_virtualization = True'
grep CurrentEL.EL "$(./getvar --arch aarch64 --emulator gem5 gem5_guest_terminal_file)"
./run --arch aarch64 --baremetal baremetal/arch/aarch64/dump_regs.c --emulator gem5 -- --param 'system.have_security = True'
grep CurrentEL.EL "$(./getvar --arch aarch64 --emulator gem5 gem5_guest_terminal_file)"
....
output:
....
19
26
19
1
2
3
CPSR.M 0x3
CPSR.M 0x3
CPSR.M 0x3
CurrentEL.EL 0x1
CurrentEL.EL 0x2
CurrentEL.EL 0x3
....
==== svc

9
baremetal/arch/aarch64/dump_regs.c
View File

@@ -6,6 +6,13 @@
int main(void) {
uint32_t sctlr_el1;
__asm__ ("mrs %0, sctlr_el1" : "=r" (sctlr_el1) : :);
printf("sctlr_el1 0x%" PRIx32 "\n", sctlr_el1);
printf("SCTLR_EL1 0x%" PRIX32 "\n", sctlr_el1);
printf("SCTLR_EL1.A 0x%" PRIX32 "\n", (sctlr_el1 >> 1) & 1);
uint64_t CurrentEL;
__asm__ ("mrs %0, CurrentEL;" : "=r" (CurrentEL) : :);
printf("CurrentEL 0x%" PRIX64 "\n", CurrentEL);
/* https://github.com/cirosantilli/linux-kernel-module-cheat#arm-exception-levels */
printf("CurrentEL.EL 0x%" PRIX64 "\n", CurrentEL >> 2);
return 0;
}

11
baremetal/arch/aarch64/el.c
View File

@@ -1,11 +0,0 @@
/* https://github.com/cirosantilli/linux-kernel-module-cheat#arm-exception-levels */
#include <stdio.h>
#include <inttypes.h>
int main(void) {
uint64_t el;
__asm__ ("mrs %0, CurrentEL;" : "=r" (el) : :);
printf("%" PRIu64 "\n", el >> 2);
return 0;
}

6
baremetal/arch/arm/dump_regs.c
View File

@@ -4,12 +4,14 @@
int main(void) {
uint32_t cpsr;
__asm__ ("mrs %0, cpsr" : "=r" (cpsr) : :);
printf("cpsr %" PRIx32 "\n", cpsr);
printf("CPSR 0x%" PRIX32 "\n", cpsr);
/* https://github.com/cirosantilli/linux-kernel-module-cheat#arm-exception-levels */
printf("CPSR.M 0x%" PRIX32 "\n", cpsr & 0xF);
/* TODO this is blowing up an exception, how to I read from it? */
/*uint32_t mvfr1;*/
/*__asm__ ("vmrs %0, mvfr1" : "=r" (mvfr1) : :);*/
/*printf("mvfr1 %" PRIx32 "\n", mvfr1);*/
/*printf("MVFR1 0x%" PRIX32 "\n", mvfr1);*/
return 0;
}

11
baremetal/arch/arm/el.c
View File

@@ -1,11 +0,0 @@
/* https://github.com/cirosantilli/linux-kernel-module-cheat#arm-exception-levels */
#include <stdio.h>
#include <inttypes.h>
int main(void) {
uint32_t cpsr;
__asm__ ("mrs %0, CPSR" : "=r" (cpsr) : :);
printf("%" PRIu32 "\n", cpsr & 0x1F);
return 0;
}