[PATCH v8 2/7] ACPI: APEI: EINJ: Enable the discovery of EINJv2 capabilities

[Zaid Alali <zaidal@os.amperecomputing.com>]

Enable the driver to show all supported error injections for EINJ
and EINJv2 at the same time. EINJv2 capabilities can be discovered
by checking the return value of get_error_type, where bit 30 set
indicates EINJv2 support.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Zaid Alali <zaidal@os.amperecomputing.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
---
 drivers/acpi/apei/apei-internal.h |  2 +-
 drivers/acpi/apei/einj-core.c     | 75 +++++++++++++++++++++++++------
 drivers/acpi/apei/einj-cxl.c      |  2 +-
 3 files changed, 63 insertions(+), 16 deletions(-)

diff --git a/drivers/acpi/apei/apei-internal.h b/drivers/acpi/apei/apei-internal.h
index cd2766c69d78..77c10a7a7a9f 100644
--- a/drivers/acpi/apei/apei-internal.h
+++ b/drivers/acpi/apei/apei-internal.h
@@ -131,7 +131,7 @@ static inline u32 cper_estatus_len(struct acpi_hest_generic_status *estatus)
 
 int apei_osc_setup(void);
 
-int einj_get_available_error_type(u32 *type);
+int einj_get_available_error_type(u32 *type, int einj_action);
 int einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2, u64 param3,
 		      u64 param4);
 int einj_cxl_rch_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
diff --git a/drivers/acpi/apei/einj-core.c b/drivers/acpi/apei/einj-core.c
index b9cdd3e44855..f018d3970de8 100644
--- a/drivers/acpi/apei/einj-core.c
+++ b/drivers/acpi/apei/einj-core.c
@@ -33,6 +33,7 @@
 #define SLEEP_UNIT_MAX		5000			/* 5ms */
 /* Firmware should respond within 1 seconds */
 #define FIRMWARE_TIMEOUT	(1 * USEC_PER_SEC)
+#define ACPI65_EINJV2_SUPP	BIT(30)
 #define ACPI5_VENDOR_BIT	BIT(31)
 #define MEM_ERROR_MASK		(ACPI_EINJ_MEMORY_CORRECTABLE | \
 				ACPI_EINJ_MEMORY_UNCORRECTABLE | \
@@ -84,6 +85,7 @@ static struct debugfs_blob_wrapper vendor_errors;
 static char vendor_dev[64];
 
 static u32 available_error_type;
+static u32 available_error_type_v2;
 
 /*
  * Some BIOSes allow parameters to the SET_ERROR_TYPE entries in the
@@ -159,13 +161,13 @@ static void einj_exec_ctx_init(struct apei_exec_context *ctx)
 			   EINJ_TAB_ENTRY(einj_tab), einj_tab->entries);
 }
 
-static int __einj_get_available_error_type(u32 *type)
+static int __einj_get_available_error_type(u32 *type, int einj_action)
 {
 	struct apei_exec_context ctx;
 	int rc;
 
 	einj_exec_ctx_init(&ctx);
-	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_ERROR_TYPE);
+	rc = apei_exec_run(&ctx, einj_action);
 	if (rc)
 		return rc;
 	*type = apei_exec_ctx_get_output(&ctx);
@@ -174,17 +176,34 @@ static int __einj_get_available_error_type(u32 *type)
 }
 
 /* Get error injection capabilities of the platform */
-int einj_get_available_error_type(u32 *type)
+int einj_get_available_error_type(u32 *type, int einj_action)
 {
 	int rc;
 
 	mutex_lock(&einj_mutex);
-	rc = __einj_get_available_error_type(type);
+	rc = __einj_get_available_error_type(type, einj_action);
 	mutex_unlock(&einj_mutex);
 
 	return rc;
 }
 
+static int einj_get_available_error_types(u32 *type1, u32 *type2)
+{
+	int rc;
+
+	rc = einj_get_available_error_type(type1, ACPI_EINJ_GET_ERROR_TYPE);
+	if (rc)
+		return rc;
+	if (*type1 & ACPI65_EINJV2_SUPP) {
+		rc = einj_get_available_error_type(type2,
+						   ACPI_EINJV2_GET_ERROR_TYPE);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
 static int einj_timedout(u64 *t)
 {
 	if ((s64)*t < SLEEP_UNIT_MIN) {
@@ -646,6 +665,7 @@ static u64 error_param2;
 static u64 error_param3;
 static u64 error_param4;
 static struct dentry *einj_debug_dir;
+static char einj_buf[32];
 static struct { u32 mask; const char *str; } const einj_error_type_string[] = {
 	{ BIT(0), "Processor Correctable" },
 	{ BIT(1), "Processor Uncorrectable non-fatal" },
@@ -662,6 +682,12 @@ static struct { u32 mask; const char *str; } const einj_error_type_string[] = {
 	{ BIT(31), "Vendor Defined Error Types" },
 };
 
+static struct { u32 mask; const char *str; } const einjv2_error_type_string[] = {
+	{ BIT(0), "EINJV2 Processor Error" },
+	{ BIT(1), "EINJV2 Memory Error" },
+	{ BIT(2), "EINJV2 PCI Express Error" },
+};
+
 static int available_error_type_show(struct seq_file *m, void *v)
 {
 
@@ -669,17 +695,22 @@ static int available_error_type_show(struct seq_file *m, void *v)
 		if (available_error_type & einj_error_type_string[pos].mask)
 			seq_printf(m, "0x%08x\t%s\n", einj_error_type_string[pos].mask,
 				   einj_error_type_string[pos].str);
-
+	if (available_error_type & ACPI65_EINJV2_SUPP) {
+		for (int pos = 0; pos < ARRAY_SIZE(einjv2_error_type_string); pos++) {
+			if (available_error_type_v2 & einjv2_error_type_string[pos].mask)
+				seq_printf(m, "V2_0x%08x\t%s\n", einjv2_error_type_string[pos].mask,
+					   einjv2_error_type_string[pos].str);
+		}
+	}
 	return 0;
 }
 
 DEFINE_SHOW_ATTRIBUTE(available_error_type);
 
-static int error_type_get(void *data, u64 *val)
+static ssize_t error_type_get(struct file *file, char __user *buf,
+				size_t count, loff_t *ppos)
 {
-	*val = error_type;
-
-	return 0;
+	return simple_read_from_buffer(buf, count, ppos, einj_buf, strlen(einj_buf));
 }
 
 bool einj_is_cxl_error_type(u64 type)
@@ -712,9 +743,23 @@ int einj_validate_error_type(u64 type)
 	return 0;
 }
 
-static int error_type_set(void *data, u64 val)
+static ssize_t error_type_set(struct file *file, const char __user *buf,
+				size_t count, loff_t *ppos)
 {
 	int rc;
+	u64 val;
+
+	memset(einj_buf, 0, sizeof(einj_buf));
+	if (copy_from_user(einj_buf, buf, count))
+		return -EFAULT;
+
+	if (strncmp(einj_buf, "V2_", 3) == 0) {
+		if (!sscanf(einj_buf, "V2_%llx", &val))
+			return -EINVAL;
+	} else {
+		if (!sscanf(einj_buf, "%llx", &val))
+			return -EINVAL;
+	}
 
 	rc = einj_validate_error_type(val);
 	if (rc)
@@ -722,11 +767,13 @@ static int error_type_set(void *data, u64 val)
 
 	error_type = val;
 
-	return 0;
+	return count;
 }
 
-DEFINE_DEBUGFS_ATTRIBUTE(error_type_fops, error_type_get, error_type_set,
-			 "0x%llx\n");
+static const struct file_operations error_type_fops = {
+	.read		= error_type_get,
+	.write		= error_type_set,
+};
 
 static int error_inject_set(void *data, u64 val)
 {
@@ -778,7 +825,7 @@ static int __init einj_probe(struct faux_device *fdev)
 		goto err_put_table;
 	}
 
-	rc = einj_get_available_error_type(&available_error_type);
+	rc = einj_get_available_error_types(&available_error_type, &available_error_type_v2);
 	if (rc)
 		goto err_put_table;
 
diff --git a/drivers/acpi/apei/einj-cxl.c b/drivers/acpi/apei/einj-cxl.c
index 78da9ae543a2..e70a416ec925 100644
--- a/drivers/acpi/apei/einj-cxl.c
+++ b/drivers/acpi/apei/einj-cxl.c
@@ -30,7 +30,7 @@ int einj_cxl_available_error_type_show(struct seq_file *m, void *v)
 	int cxl_err, rc;
 	u32 available_error_type = 0;
 
-	rc = einj_get_available_error_type(&available_error_type);
+	rc = einj_get_available_error_type(&available_error_type, ACPI_EINJ_GET_ERROR_TYPE);
 	if (rc)
 		return rc;
 
-- 
2.43.0