[PATCH] powerpc/le: enable RTAS events support

[Greg Kurz]

The current kernel code assumes big endian and parses RTAS events all
wrong. The most visible effect is that we cannot honor EPOW events,
meaning, for example, we cannot shut down a guest properly from the
hypervisor.

This patch fixes that.

Signed-off-by: Greg Kurz <gkurz at linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/rtas.h      |   46 ++++++++++++++++++++++++++++++++++
 arch/powerpc/kernel/rtas.c           |   11 ++++----
 arch/powerpc/kernel/rtasd.c          |    8 ++++--
 arch/powerpc/platforms/pseries/ras.c |    3 +-
 4 files changed, 59 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/include/asm/rtas.h b/arch/powerpc/include/asm/rtas.h
index 9bd52c6..8bb99d0 100644
--- a/arch/powerpc/include/asm/rtas.h
+++ b/arch/powerpc/include/asm/rtas.h
@@ -150,15 +150,37 @@ struct rtas_suspend_me_data {
 #define RTAS_VECTOR_EXTERNAL_INTERRUPT	0x500
 
 struct rtas_error_log {
+#ifdef __BIG_ENDIAN__
+	/* Byte 0 */
 	unsigned long version:8;		/* Architectural version */
+	/* Byte 1 */
 	unsigned long severity:3;		/* Severity level of error */
 	unsigned long disposition:2;		/* Degree of recovery */
 	unsigned long extended:1;		/* extended log present? */
 	unsigned long /* reserved */ :2;	/* Reserved for future use */
+	/* Byte 2 */
 	unsigned long initiator:4;		/* Initiator of event */
 	unsigned long target:4;			/* Target of failed operation */
+	/* Byte 3 */
 	unsigned long type:8;			/* General event or error*/
+	/* Byte 4 */
 	unsigned long extended_log_length:32;	/* length in bytes */
+#else
+	/* Byte 0 */
+	unsigned long version:8;
+	/* Byte 1 */
+	unsigned long :2;
+	unsigned long extended:1;
+	unsigned long disposition:2;
+	unsigned long severity:3;
+	unsigned long target:4;
+	/* Byte 2 */
+	unsigned long initiator:4;
+	/* Byte 3 */
+	unsigned long type:8;
+	/* Byte 4 */
+	unsigned long extended_log_length:32;
+#endif
 	unsigned char buffer[1];		/* Start of extended log */
 						/* Variable length.      */
 };
@@ -171,6 +193,7 @@ struct rtas_error_log {
  * from "buffer" field of struct rtas_error_log defined above.
  */
 struct rtas_ext_event_log_v6 {
+#ifdef __BIG_ENDIAN__
 	/* Byte 0 */
 	uint32_t log_valid:1;		/* 1:Log valid */
 	uint32_t unrecoverable_error:1;	/* 1:Unrecoverable error */
@@ -200,6 +223,29 @@ struct rtas_ext_event_log_v6 {
 	uint32_t company_id;		/* Company ID of the company	*/
 					/* that defines the format for	*/
 					/* the vendor specific log type	*/
+#else
+	/* Byte 0 */
+	uint32_t :1;
+	uint32_t big_endian:1;
+	uint32_t new_log:1;
+	uint32_t predictive_error:1;
+	uint32_t degraded_operation:1;
+	uint32_t recoverable_error:1;
+	uint32_t unrecoverable_error:1;
+	uint32_t log_valid:1;
+	/* Byte 1 */
+	uint32_t :8;
+	/* Byte 2 */
+	uint32_t log_format:4;
+	uint32_t :3;
+	uint32_t powerpc_format:1;
+	/* Byte 3 */
+	uint32_t :8;
+	/* Byte 4-11 */
+	uint8_t reserved[8];
+	/* Byte 12-15 */
+	uint32_t company_id;
+#endif
 	/* Byte 16-end of log */
 	uint8_t vendor_log[1];		/* Start of vendor specific log	*/
 					/* Variable length.		*/
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index f386296..e18ab12 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -993,21 +993,22 @@ struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
 		(struct rtas_ext_event_log_v6 *)log->buffer;
 	struct pseries_errorlog *sect;
 	unsigned char *p, *log_end;
+	uint32_t extended_log_length = be32_to_cpu(log->extended_log_length);
 
 	/* Check that we understand the format */
-	if (log->extended_log_length < sizeof(struct rtas_ext_event_log_v6) ||
+	if (extended_log_length < sizeof(struct rtas_ext_event_log_v6) ||
 	    ext_log->log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
-	    ext_log->company_id != RTAS_V6EXT_COMPANY_ID_IBM)
+	    be32_to_cpu(ext_log->company_id) != RTAS_V6EXT_COMPANY_ID_IBM)
 		return NULL;
 
-	log_end = log->buffer + log->extended_log_length;
+	log_end = log->buffer + extended_log_length;
 	p = ext_log->vendor_log;
 
 	while (p < log_end) {
 		sect = (struct pseries_errorlog *)p;
-		if (sect->id == section_id)
+		if (be16_to_cpu(sect->id) == section_id)
 			return sect;
-		p += sect->length;
+		p += be16_to_cpu(sect->length);
 	}
 
 	return NULL;
diff --git a/arch/powerpc/kernel/rtasd.c b/arch/powerpc/kernel/rtasd.c
index 1130c53..1987825 100644
--- a/arch/powerpc/kernel/rtasd.c
+++ b/arch/powerpc/kernel/rtasd.c
@@ -159,14 +159,16 @@ static int log_rtas_len(char * buf)
 {
 	int len;
 	struct rtas_error_log *err;
+	uint32_t extended_log_length;
 
 	/* rtas fixed header */
 	len = 8;
 	err = (struct rtas_error_log *)buf;
-	if (err->extended && err->extended_log_length) {
+	extended_log_length = be32_to_cpu(err->extended_log_length);
+	if (err->extended && extended_log_length) {
 
 		/* extended header */
-		len += err->extended_log_length;
+		len += extended_log_length;
 	}
 
 	if (rtas_error_log_max == 0)
@@ -298,7 +300,7 @@ static void handle_rtas_event(const struct rtas_error_log *log)
 		 * the scope for calling rtas update-nodes.
 		 */
 		if (prrn_is_enabled())
-			prrn_schedule_update(log->extended_log_length);
+			prrn_schedule_update(be32_to_cpu(log->extended_log_length));
 	}
 
 	return;
diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c
index 721c058..39e7557 100644
--- a/arch/powerpc/platforms/pseries/ras.c
+++ b/arch/powerpc/platforms/pseries/ras.c
@@ -306,7 +306,8 @@ static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs)
 	} else {
 		int len;
 
-		len = max_t(int, 8+h->extended_log_length, RTAS_ERROR_LOG_MAX);
+		len = max_t(int, 8+be32_to_cpu(h->extended_log_length),
+			    RTAS_ERROR_LOG_MAX);
 		memset(global_mce_data_buf, 0, RTAS_ERROR_LOG_MAX);
 		memcpy(global_mce_data_buf, h, len);
 		errhdr = (struct rtas_error_log *)global_mce_data_buf;