Add workaround for Fujitsu A64FX erratum 010001

Signed-off-by: Zhang Lei <zhang....@jp.fujitsu.com>
---
 Documentation/arm64/silicon-errata.txt |  1 +
 arch/arm64/Kconfig                     | 22 ++++++++++++++++++++++
 arch/arm64/include/asm/cpucaps.h       |  3 ++-
 arch/arm64/include/asm/cputype.h       |  4 ++++
 arch/arm64/kernel/cpu_errata.c         |  8 ++++++++
 arch/arm64/kernel/entry.S              | 16 ++++++++++++++++
 arch/arm64/mm/fault.c                  | 16 +++++++++++++++-
 arch/arm64/mm/proc.S                   | 20 ++++++++++++++++++++
 8 files changed, 88 insertions(+), 2 deletions(-)

diff --git a/Documentation/arm64/silicon-errata.txt 
b/Documentation/arm64/silicon-errata.txt
index 1f09d04..26d64e9 100644
--- a/Documentation/arm64/silicon-errata.txt
+++ b/Documentation/arm64/silicon-errata.txt
@@ -80,3 +80,4 @@ stable kernels.
 | Qualcomm Tech. | Falkor v1       | E1009           | 
QCOM_FALKOR_ERRATUM_1009    |
 | Qualcomm Tech. | QDF2400 ITS     | E0065           | 
QCOM_QDF2400_ERRATUM_0065   |
 | Qualcomm Tech. | Falkor v{1,2}   | E1041           | 
QCOM_FALKOR_ERRATUM_1041    |
+| Fujitsu        | A64FX           | E#010001        | FUJITSU_ERRATUM_010001  
    |
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a4168d3..60e193f
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -643,6 +643,28 @@ config QCOM_FALKOR_ERRATUM_E1041
 
          If unsure, say Y.
 
+config FUJITSU_ERRATUM_010001
+       bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
+       default y
+       help
+         This option adds workaround for Fujitsu-A64FX erratum E#010001.
+         On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory 
accesses
+         may cause undefined fault (Data abort, DFSC=0b111111).
+         This fault occurs under a specific hardware condition when a 
load/store
+          instruction perform an address translation using:
+         case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
+         case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
+         case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
+         case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
+
+         The workaround is to set '0' to TCR_ELx.NFD1 at kernel-entry,
+         and set '1' at kernel-exit. And also replace the fault handler
+         for Data abort DFSC=0b111111 with a new one to ignore this
+         undefined fault.
+         Only affect the Fujitsu-A64FX.
+
+         If unsure, say Y.
+
 endmenu
 
 
diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
index 82e9099..3a0b375 100644
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -60,7 +60,8 @@
 #define ARM64_HAS_ADDRESS_AUTH_IMP_DEF         39
 #define ARM64_HAS_GENERIC_AUTH_ARCH            40
 #define ARM64_HAS_GENERIC_AUTH_IMP_DEF         41
+#define ARM64_WORKAROUND_FUJITSU_A64FX_0100001 42
 
-#define ARM64_NCAPS                            42
+#define ARM64_NCAPS                            43
 
 #endif /* __ASM_CPUCAPS_H */
diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
index 951ed1a..70203f9 100644
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -76,6 +76,7 @@
 #define ARM_CPU_IMP_BRCM               0x42
 #define ARM_CPU_IMP_QCOM               0x51
 #define ARM_CPU_IMP_NVIDIA             0x4E
+#define ARM_CPU_IMP_FUJITSU            0x46
 
 #define ARM_CPU_PART_AEM_V8            0xD0F
 #define ARM_CPU_PART_FOUNDATION                0xD00
@@ -104,6 +105,8 @@
 #define NVIDIA_CPU_PART_DENVER         0x003
 #define NVIDIA_CPU_PART_CARMEL         0x004
 
+#define FUJITSU_CPU_PART_A64FX         0x001
+
 #define MIDR_CORTEX_A53 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, 
ARM_CPU_PART_CORTEX_A53)
 #define MIDR_CORTEX_A57 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, 
ARM_CPU_PART_CORTEX_A57)
 #define MIDR_CORTEX_A72 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, 
ARM_CPU_PART_CORTEX_A72)
@@ -122,6 +125,7 @@
 #define MIDR_QCOM_KRYO MIDR_CPU_MODEL(ARM_CPU_IMP_QCOM, QCOM_CPU_PART_KRYO)
 #define MIDR_NVIDIA_DENVER MIDR_CPU_MODEL(ARM_CPU_IMP_NVIDIA, 
NVIDIA_CPU_PART_DENVER)
 #define MIDR_NVIDIA_CARMEL MIDR_CPU_MODEL(ARM_CPU_IMP_NVIDIA, 
NVIDIA_CPU_PART_CARMEL)
+#define MIDR_FUJITSU_A64FX MIDR_CPU_MODEL(ARM_CPU_IMP_FUJITSU, 
FUJITSU_CPU_PART_A64FX)
 
 #ifndef __ASSEMBLY__
 
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 9950bb0..fc0737f 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -739,6 +739,14 @@ static bool has_ssbd_mitigation(const struct 
arm64_cpu_capabilities *entry,
                ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 2, 0),
        },
 #endif
+#ifdef CONFIG_FUJITSU_ERRATUM_010001
+       {
+               .desc = "Fujitsu erratum 010001",
+               .capability = ARM64_WORKAROUND_FUJITSU_A64FX_0100001,
+               ERRATA_MIDR_RANGE(MIDR_FUJITSU_A64FX, 0, 0, 1, 0),
+       },
+#endif
+
        {
        }
 };
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 0ec0c46..34a4f44
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -940,6 +940,14 @@ alternative_if ARM64_WORKAROUND_QCOM_FALKOR_E1003
        dsb     nsh
 alternative_else_nop_endif
 #endif /* CONFIG_QCOM_FALKOR_ERRATUM_1003 */
+#ifdef CONFIG_FUJITSU_CPU_PART_A64FX
+alternative_if ARM64_WORKAROUND_FUJITSU_A64FX_0100001
+       mrs     \tmp, tcr_el1
+       and     \tmp, \tmp, #0xffbfffffffffffff
+       msr     tcr_el1,\tmp
+       isb
+alternative_else_nop_endif
+#endif /* CONFIG_FUJITSU_CPU_PART_A64FX */
        .endm
 
        .macro tramp_unmap_kernel, tmp
@@ -952,6 +960,14 @@ alternative_else_nop_endif
         * it's only needed by Cavium ThunderX, which requires KPTI to be
         * disabled.
         */
+#ifdef CONFIG_FUJITSU_CPU_PART_A64FX
+alternative_if ARM64_WORKAROUND_FUJITSU_A64FX_0100001
+       mrs     \tmp, tcr_el1
+       orr     \tmp, \tmp, #0x40000000000000
+       msr     tcr_el1,\tmp
+       isb
+alternative_else_nop_endif
+#endif /* CONFIG_FUJITSU_CPU_PART_A64FX */
        .endm
 
        .macro tramp_ventry, regsize = 64
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index efb7b2c..1bf0377
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -666,6 +666,20 @@ static int do_sea(unsigned long addr, unsigned int esr, 
struct pt_regs *regs)
        return 0;
 }
 
+static int do_bad_unknown_63(unsigned long addr, unsigned int esr, struct 
pt_regs *regs)
+{
+       /*
+        * On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1),
+        * memory accesses may spuriously trigger data aborts with
+        * DFSC=0b111111.
+        */
+       if (IS_ENABLED(CONFIG_FUJITSU_ERRATUM_010001) &&
+               cpus_have_cap(ARM64_WORKAROUND_FUJITSU_A64FX_0100001))
+                       return 0;
+       return do_bad(addr, esr, regs);
+}
+
+
 static const struct fault_info fault_info[] = {
        { do_bad,               SIGKILL, SI_KERNEL,     "ttbr address size 
fault"       },
        { do_bad,               SIGKILL, SI_KERNEL,     "level 1 address size 
fault"    },
@@ -730,7 +744,7 @@ static int do_sea(unsigned long addr, unsigned int esr, 
struct pt_regs *regs)
        { do_bad,               SIGKILL, SI_KERNEL,     "unknown 60"            
        },
        { do_bad,               SIGKILL, SI_KERNEL,     "section domain fault"  
        },
        { do_bad,               SIGKILL, SI_KERNEL,     "page domain fault"     
        },
-       { do_bad,               SIGKILL, SI_KERNEL,     "unknown 63"            
        },
+       { do_bad_unknown_63,    SIGKILL, SI_KERNEL,     "unknown 63"            
        },
 };
 
 int handle_guest_sea(phys_addr_t addr, unsigned int esr)
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 73886a5..75f7d99
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -453,9 +453,29 @@ ENTRY(__cpu_setup)
         * Set/prepare TCR and TTBR. We use 512GB (39-bit) address range for
         * both user and kernel.
         */
+#ifdef CONFIG_FUJITSU_ERRATUM_010001
        ldr     x10, =TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \
                        TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \
                        TCR_TBI0 | TCR_A1 | TCR_KASAN_FLAGS
+       /* Can use x19/x20/x5 */
+       mrs     x19, midr_el1
+       /* ERRATA_MIDR_RANGE(MIDR_FUJITSU_A64FX, 0, 0, 1, 0) */
+       mov     w20, #0x10      //#16
+       movk    w20, #0x460f, lsl #16
+       mov     w5, #0xffefffff
+       and     w19, w5, w19
+       /* cmp midr_el1 with ERRATA_MIDR_RANGE(MIDR_FUJITSU_A64FX, 0, 0, 1, 0) 
*/
+       cmp     w19, w20
+       b.ne    2f
+       ldr     x10, =TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \
+                       TCR_TG_FLAGS | TCR_ASID16 | \
+                       TCR_TBI0 | TCR_A1 | TCR_KASAN_FLAGS
+2:     nop
+#else
+       ldr     x10, =TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \
+                       TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \
+                       TCR_TBI0 | TCR_A1 | TCR_KASAN_FLAGS
+#endif
 
 #ifdef CONFIG_ARM64_USER_VA_BITS_52
        ldr_l           x9, vabits_user
-- 
1.8.3.1

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