ARM CPUs fetch instructions in little-endian.
smpboot[] encoded instructions are written in little-endian.
We call tswap32() on the array. tswap32 function swap a 32-bit
value if the target endianness doesn't match the host one.
Otherwise it is a NOP.
* On a little-endian host, the array is stored as it. tswap32()
is a NOP, and the vCPU fetches the instructions as it, in
little-endian.
* On a big-endian host, the array is stored as it. tswap32()
swap the instructions to little-endian, and the vCPU fetches
the instructions as it, in little-endian.
Using tswap() on system emulation is a bit odd: while the target
particularities might change the system emulation, the host ones
(such its endianness) shouldn't interfere.
We can simplify by using const_le32() to always store the
instructions in the array in little-endian, removing the need
for the dubious tswap().
Signed-off-by: Philippe Mathieu-Daudé <phi...@linaro.org>
---
hw/arm/exynos4210.c | 48 ++++++++++++++++++++-------------------------
1 file changed, 21 insertions(+), 27 deletions(-)
diff --git a/hw/arm/exynos4210.c b/hw/arm/exynos4210.c
index 8dafa2215b..89ee83456d 100644
--- a/hw/arm/exynos4210.c
+++ b/hw/arm/exynos4210.c
@@ -468,35 +468,29 @@ static const MemoryRegionOps
exynos4210_chipid_and_omr_ops = {
}
};
-void exynos4210_write_secondary(ARMCPU *cpu,
- const struct arm_boot_info *info)
+void exynos4210_write_secondary(ARMCPU *cpu, const struct arm_boot_info *info)
{
- int n;
- uint32_t smpboot[] = {
- 0xe59f3034, /* ldr r3, External gic_cpu_if */
- 0xe59f2034, /* ldr r2, Internal gic_cpu_if */
- 0xe59f0034, /* ldr r0, startaddr */
- 0xe3a01001, /* mov r1, #1 */
- 0xe5821000, /* str r1, [r2] */
- 0xe5831000, /* str r1, [r3] */
- 0xe3a010ff, /* mov r1, #0xff */
- 0xe5821004, /* str r1, [r2, #4] */
- 0xe5831004, /* str r1, [r3, #4] */
- 0xf57ff04f, /* dsb */
- 0xe320f003, /* wfi */
- 0xe5901000, /* ldr r1, [r0] */
- 0xe1110001, /* tst r1, r1 */
- 0x0afffffb, /* beq <wfi> */
- 0xe12fff11, /* bx r1 */
- EXYNOS4210_EXT_GIC_CPU_BASE_ADDR,
- 0, /* gic_cpu_if: base address of Internal GIC CPU interface
*/
- 0 /* bootreg: Boot register address is held here */
+ const uint32_t smpboot[] = {
+ const_le32(0xe59f3034), /* ldr r3, External gic_cpu_if */
+ const_le32(0xe59f2034), /* ldr r2, Internal gic_cpu_if */
+ const_le32(0xe59f0034), /* ldr r0, startaddr */
+ const_le32(0xe3a01001), /* mov r1, #1 */
+ const_le32(0xe5821000), /* str r1, [r2] */
+ const_le32(0xe5831000), /* str r1, [r3] */
+ const_le32(0xe3a010ff), /* mov r1, #0xff */
+ const_le32(0xe5821004), /* str r1, [r2, #4] */
+ const_le32(0xe5831004), /* str r1, [r3, #4] */
+ const_le32(0xf57ff04f), /* dsb */
+ const_le32(0xe320f003), /* wfi */
+ const_le32(0xe5901000), /* ldr r1, [r0] */
+ const_le32(0xe1110001), /* tst r1, r1 */
+ const_le32(0x0afffffb), /* beq <wfi> */
+ const_le32(0xe12fff11), /* bx r1 */
+ const_le32(EXYNOS4210_EXT_GIC_CPU_BASE_ADDR),
+ cpu_to_le32(info->gic_cpu_if_addr), /* base address of Internal GIC
CPU interface */
+ cpu_to_le32(info->smp_bootreg_addr) /* Boot register address is held
here */
};
- smpboot[ARRAY_SIZE(smpboot) - 1] = info->smp_bootreg_addr;
- smpboot[ARRAY_SIZE(smpboot) - 2] = info->gic_cpu_if_addr;
- for (n = 0; n < ARRAY_SIZE(smpboot); n++) {
- smpboot[n] = tswap32(smpboot[n]);
- }
+
rom_add_blob_fixed("smpboot", smpboot, sizeof(smpboot),
info->smp_loader_start);
}
--
2.38.1
