[RFC V3 09/13] arm64/mm: Add __cpu_secondary_check52bitpa()
From: Anshuman Khandual <hidden>
Date: 2021-09-30 10:34:59
Also in:
lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
FEAT_LPA2 enabled systems needs to test ID_AA64MMFR0.TGRAN value to ensure that 52 bit PA range is supported across all secondary CPUs both for 4K and 16K configs. This adds a new __cpu_secondary_check52bitva check along with a corresponding reason code CPU_STUCK_REASON_52_BIT_PA. This will identify the exact reason in case the system gets stuck after detecting a secondary CPU that does not support 52 bit PA. Signed-off-by: Anshuman Khandual <redacted> --- arch/arm64/include/asm/smp.h | 1 + arch/arm64/kernel/head.S | 21 +++++++++++++++++++++ arch/arm64/kernel/smp.c | 2 ++ 3 files changed, 24 insertions(+)
diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h
index fc55f5a..e5ff305 100644
--- a/arch/arm64/include/asm/smp.h
+++ b/arch/arm64/include/asm/smp.h@@ -22,6 +22,7 @@ #define CPU_STUCK_REASON_52_BIT_VA (UL(1) << CPU_STUCK_REASON_SHIFT) #define CPU_STUCK_REASON_NO_GRAN (UL(2) << CPU_STUCK_REASON_SHIFT) +#define CPU_STUCK_REASON_52_BIT_PA (UL(3) << CPU_STUCK_REASON_SHIFT) #ifndef __ASSEMBLY__
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index ab21aac..0b48e4c 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S@@ -667,6 +667,7 @@ SYM_FUNC_START_LOCAL(secondary_startup) */ bl switch_to_vhe bl __cpu_secondary_check52bitva + bl __cpu_secondary_check52bitpa bl __cpu_setup // initialise processor adrp x1, swapper_pg_dir bl __enable_mmu
@@ -770,6 +771,26 @@ SYM_FUNC_START(__cpu_secondary_check52bitva) 2: ret SYM_FUNC_END(__cpu_secondary_check52bitva) +SYM_FUNC_START(__cpu_secondary_check52bitpa) +#ifdef CONFIG_ARM64_PA_BITS_52_LPA2 + ldr_l x0, arm64_lpa2_enabled + cmp x2, #1 + b.ne 2f + + mrs x0, ID_AA64MMFR0_EL1 + ubfx x0, x0, #ID_AA64MMFR0_TGRAN_SHIFT, 4 + cmp x0, #ID_AA64MMFR0_TGRAN_LPA2 + b.ge 2f + + update_early_cpu_boot_status \ + CPU_STUCK_IN_KERNEL | CPU_STUCK_REASON_52_BIT_PA, x0, x1 +1: wfe + wfi + b 1b +#endif +2: ret +SYM_FUNC_END(__cpu_secondary_check52bitpa) + SYM_FUNC_START_LOCAL(__no_granule_support) /* Indicate that this CPU can't boot and is stuck in the kernel */ update_early_cpu_boot_status \
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 6f6ff072..a8d08d1 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c@@ -164,6 +164,8 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) if (status & CPU_STUCK_REASON_NO_GRAN) { pr_crit("CPU%u: does not support %luK granule\n", cpu, PAGE_SIZE / SZ_1K); + if (status & CPU_STUCK_REASON_52_BIT_PA) + pr_crit("CPU%u: does not support 52-bit PAs\n", cpu); } cpus_stuck_in_kernel++; break;
--
2.7.4
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