[PATCH v7 03/16] arm64: ras: Unify the read/write interface for system and MMIO registers
From: Ruidong Tian
Date: Tue Jun 02 2026 - 03:19:45 EST
ARM RAS error records are reachable either through system registers
(PE-affine sources) or through memory-mapped windows (off-core
sources), depending on the AEST interface type. Hard-coding the
choice at every call site would scatter that knowledge across the
driver and double every future change.
Introduce a ras_access ops table that hides the transport behind a
single read/write contract, so all later error handling, masking and
injection code is access-method-agnostic and can be reasoned about as
plain register operations.
Signed-off-by: Ruidong Tian <tianruidong@xxxxxxxxxxxxxxxxx>
---
drivers/acpi/arm64/aest.c | 3 +-
drivers/ras/arm64/ras-core.c | 5 +-
drivers/ras/arm64/ras.h | 94 ++++++++++++++++++++++++++++++++++++
3 files changed, 100 insertions(+), 2 deletions(-)
diff --git a/drivers/acpi/arm64/aest.c b/drivers/acpi/arm64/aest.c
index 8cf24467d0c2..3a813fe7047c 100644
--- a/drivers/acpi/arm64/aest.c
+++ b/drivers/acpi/arm64/aest.c
@@ -93,6 +93,7 @@ aest_init_node_props(struct acpi_aest_hdr *hdr, struct property_entry *props,
}
props[(*p)++] = PROPERTY_ENTRY_U8("arm,node-type", hdr->type);
+ props[(*p)++] = PROPERTY_ENTRY_U8("arm,interface-type", interface->type);
props[(*p)++] = PROPERTY_ENTRY_U8("arm,group-format",
interface->group_format);
props[(*p)++] = PROPERTY_ENTRY_U32("arm,error-records-count",
@@ -121,7 +122,7 @@ aest_init_node_props(struct acpi_aest_hdr *hdr, struct property_entry *props,
static int __init
aest_create_node_fwnode(struct acpi_aest_hdr *hdr, struct platform_device *pdev)
{
- struct property_entry props[10] = { };
+ struct property_entry props[11] = { };
int p = 0;
int ret;
diff --git a/drivers/ras/arm64/ras-core.c b/drivers/ras/arm64/ras-core.c
index b5448f4a841f..47ab78cc88d7 100644
--- a/drivers/ras/arm64/ras-core.c
+++ b/drivers/ras/arm64/ras-core.c
@@ -51,6 +51,7 @@ static int ras_init_record(struct ras_record *record, int i, struct ras_node *no
if (node->base)
record->regs_base = node->base + sizeof(struct ras_ext_regs) * i;
+ record->access = &ras_access[node->access_type];
record->index = i;
record->node = node;
@@ -152,6 +153,7 @@ static struct ras_node *ras_init_node(struct platform_device *pdev)
node->dev = &pdev->dev;
ret = ret ?: device_property_read_u8(dev, "arm,node-type", &node->type);
+ ret = ret ?: device_property_read_u8(dev, "arm,interface-type", &node->access_type);
ret = ret ?: device_property_read_u8(dev, "arm,group-format", &node->group_format);
ret = ret ?: device_property_read_u32(dev, "arm,interface-flags", &node->flags);
ret = ret ?: device_property_read_u32(dev, "arm,error-records-count", &node->record_count);
@@ -219,7 +221,8 @@ static struct ras_node *ras_init_node(struct platform_device *pdev)
if (ret)
return ERR_PTR(ret);
}
- ras_node_dbg(node, "base: %llx\n", node->addr);
+ ras_node_dbg(node, "base: %llx, access_type: %s\n",
+ node->addr, node->access_type ? "MMIO" : "Register");
return node;
}
diff --git a/drivers/ras/arm64/ras.h b/drivers/ras/arm64/ras.h
index 3d83f8b26da7..94ffeb83b251 100644
--- a/drivers/ras/arm64/ras.h
+++ b/drivers/ras/arm64/ras.h
@@ -11,6 +11,11 @@
#include <linux/acpi_aest.h>
#include <asm/ras.h>
+#define record_read(record, offset) \
+ ((record)->access->read((record)->regs_base, (offset)))
+#define record_write(record, offset, val) \
+ ((record)->access->write((record)->regs_base, (offset), (val)))
+
#define ras_node_err(__node, format, ...) \
dev_err((__node)->dev, "%s: " format, (__node)->name, \
##__VA_ARGS__)
@@ -41,10 +46,25 @@
#define ERXGROUP_16K_ERRGSR_NUM 4
#define ERXGROUP_64K_ERRGSR_NUM 14
+#define ERXFR 0x0
+#define ERXCTLR 0x8
+#define ERXSTATUS 0x10
+#define ERXADDR 0x18
+#define ERXMISC0 0x20
+#define ERXMISC1 0x28
+#define ERXMISC2 0x30
+#define ERXMISC3 0x38
+
+struct ras_access {
+ u64 (*read)(void __iomem *base, u32 offset);
+ void (*write)(void __iomem *base, u32 offset, u64 val);
+};
+
struct ras_record {
char *name;
void __iomem *regs_base;
struct ras_node *node;
+ const struct ras_access *access;
int index;
};
@@ -98,7 +118,81 @@ struct ras_node {
u32 flags;
u8 type;
+ u8 access_type;
u8 group_format;
};
+#define CASE_READ(res, x) \
+ case (x): { \
+ res = read_sysreg_s(SYS_##x##_EL1); \
+ break; \
+ }
+
+#define CASE_WRITE(val, x) \
+ case (x): { \
+ write_sysreg_s((val), SYS_##x##_EL1); \
+ break; \
+ }
+
+static inline u64 ras_sysreg_read(void __iomem *base __always_unused, u32 offset)
+{
+ u64 res;
+
+ switch (offset) {
+ CASE_READ(res, ERXFR)
+ CASE_READ(res, ERXCTLR)
+ CASE_READ(res, ERXSTATUS)
+ CASE_READ(res, ERXADDR)
+ CASE_READ(res, ERXMISC0)
+ CASE_READ(res, ERXMISC1)
+ CASE_READ(res, ERXMISC2)
+ CASE_READ(res, ERXMISC3)
+ default:
+ res = 0;
+ }
+ return res;
+}
+
+static inline void ras_sysreg_write(void __iomem *base __always_unused, u32 offset, u64 val)
+{
+ switch (offset) {
+ CASE_WRITE(val, ERXFR)
+ CASE_WRITE(val, ERXCTLR)
+ CASE_WRITE(val, ERXSTATUS)
+ CASE_WRITE(val, ERXADDR)
+ CASE_WRITE(val, ERXMISC0)
+ CASE_WRITE(val, ERXMISC1)
+ CASE_WRITE(val, ERXMISC2)
+ CASE_WRITE(val, ERXMISC3)
+ default:
+ return;
+ }
+}
+
+static inline u64 ras_iomem_read(void __iomem *base, u32 offset)
+{
+ return readq_relaxed(base + offset);
+}
+
+static inline void ras_iomem_write(void __iomem *base, u32 offset, u64 val)
+{
+ writeq_relaxed(val, base + offset);
+}
+
+/* access type is decided by AEST interface type. */
+static const struct ras_access ras_access[] = {
+ [ACPI_AEST_NODE_SYSTEM_REGISTER] = {
+ .read = ras_sysreg_read,
+ .write = ras_sysreg_write,
+ },
+ [ACPI_AEST_NODE_MEMORY_MAPPED] = {
+ .read = ras_iomem_read,
+ .write = ras_iomem_write,
+ },
+ [ACPI_AEST_NODE_SINGLE_RECORD_MEMORY_MAPPED] = {
+ .read = ras_iomem_read,
+ .write = ras_iomem_write,
+ },
+};
+
#endif /* _DRIVERS_RAS_ARM64_RAS_H_ */
--
2.51.2.612.gdc70283dfc