[PATCH v2 2/2] pseries/mce: Refactor the pseries mce handling code

[Ganesh Goudar]

Now that we are no longer switching on the mmu in realmode
mce handler, Revert the commit 4ff753feab02("powerpc/pseries:
Avoid using addr_to_pfn in real mode") partially, which
introduced functions mce_handle_err_virtmode/realmode() to
separate mce handler code which needed translation to enabled.

Signed-off-by: Ganesh Goudar <ganeshgr at linux.ibm.com>
---
 arch/powerpc/platforms/pseries/ras.c | 122 +++++++++++----------------
 1 file changed, 49 insertions(+), 73 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c
index 8613f9cc5798..62e1519b8355 100644
--- a/arch/powerpc/platforms/pseries/ras.c
+++ b/arch/powerpc/platforms/pseries/ras.c
@@ -511,58 +511,17 @@ int pSeries_system_reset_exception(struct pt_regs *regs)
 	return 0; /* need to perform reset */
 }
 
-static int mce_handle_err_realmode(int disposition, u8 error_type)
-{
-#ifdef CONFIG_PPC_BOOK3S_64
-	if (disposition == RTAS_DISP_NOT_RECOVERED) {
-		switch (error_type) {
-		case	MC_ERROR_TYPE_ERAT:
-			flush_erat();
-			disposition = RTAS_DISP_FULLY_RECOVERED;
-			break;
-		case	MC_ERROR_TYPE_SLB:
-			/*
-			 * Store the old slb content in paca before flushing.
-			 * Print this when we go to virtual mode.
-			 * There are chances that we may hit MCE again if there
-			 * is a parity error on the SLB entry we trying to read
-			 * for saving. Hence limit the slb saving to single
-			 * level of recursion.
-			 */
-			if (local_paca->in_mce == 1)
-				slb_save_contents(local_paca->mce_faulty_slbs);
-			flush_and_reload_slb();
-			disposition = RTAS_DISP_FULLY_RECOVERED;
-			break;
-		default:
-			break;
-		}
-	} else if (disposition == RTAS_DISP_LIMITED_RECOVERY) {
-		/* Platform corrected itself but could be degraded */
-		pr_err("MCE: limited recovery, system may be degraded\n");
-		disposition = RTAS_DISP_FULLY_RECOVERED;
-	}
-#endif
-	return disposition;
-}
-
-static int mce_handle_err_virtmode(struct pt_regs *regs,
-				   struct rtas_error_log *errp,
-				   struct pseries_mc_errorlog *mce_log,
-				   int disposition)
+static int mce_handle_error(struct pt_regs *regs, struct rtas_error_log *errp)
 {
 	struct mce_error_info mce_err = { 0 };
+	unsigned long eaddr = 0, paddr = 0;
+	struct pseries_errorlog *pseries_log;
+	struct pseries_mc_errorlog *mce_log;
+	int disposition = rtas_error_disposition(errp);
 	int initiator = rtas_error_initiator(errp);
 	int severity = rtas_error_severity(errp);
-	unsigned long eaddr = 0, paddr = 0;
 	u8 error_type, err_sub_type;
 
-	if (!mce_log)
-		goto out;
-
-	error_type = mce_log->error_type;
-	err_sub_type = rtas_mc_error_sub_type(mce_log);
-
 	if (initiator == RTAS_INITIATOR_UNKNOWN)
 		mce_err.initiator = MCE_INITIATOR_UNKNOWN;
 	else if (initiator == RTAS_INITIATOR_CPU)
@@ -588,6 +547,8 @@ static int mce_handle_err_virtmode(struct pt_regs *regs,
 		mce_err.severity = MCE_SEV_SEVERE;
 	else if (severity == RTAS_SEVERITY_ERROR)
 		mce_err.severity = MCE_SEV_SEVERE;
+	else if (severity == RTAS_SEVERITY_FATAL)
+		mce_err.severity = MCE_SEV_FATAL;
 	else
 		mce_err.severity = MCE_SEV_FATAL;
 
@@ -599,7 +560,18 @@ static int mce_handle_err_virtmode(struct pt_regs *regs,
 	mce_err.error_type = MCE_ERROR_TYPE_UNKNOWN;
 	mce_err.error_class = MCE_ECLASS_UNKNOWN;
 
-	switch (error_type) {
+	if (!rtas_error_extended(errp))
+		goto out;
+
+	pseries_log = get_pseries_errorlog(errp, PSERIES_ELOG_SECT_ID_MCE);
+	if (!pseries_log)
+		goto out;
+
+	mce_log = (struct pseries_mc_errorlog *)pseries_log->data;
+	error_type = mce_log->error_type;
+	err_sub_type = rtas_mc_error_sub_type(mce_log);
+
+	switch (mce_log->error_type) {
 	case MC_ERROR_TYPE_UE:
 		mce_err.error_type = MCE_ERROR_TYPE_UE;
 		mce_common_process_ue(regs, &mce_err);
@@ -692,41 +664,45 @@ static int mce_handle_err_virtmode(struct pt_regs *regs,
 		mce_err.error_type = MCE_ERROR_TYPE_DCACHE;
 		break;
 	case MC_ERROR_TYPE_I_CACHE:
-		mce_err.error_type = MCE_ERROR_TYPE_ICACHE;
+		mce_err.error_type = MCE_ERROR_TYPE_DCACHE;
 		break;
 	case MC_ERROR_TYPE_UNKNOWN:
 	default:
 		mce_err.error_type = MCE_ERROR_TYPE_UNKNOWN;
 		break;
 	}
+
+#ifdef CONFIG_PPC_BOOK3S_64
+	if (disposition == RTAS_DISP_NOT_RECOVERED) {
+		switch (error_type) {
+		case	MC_ERROR_TYPE_SLB:
+		case	MC_ERROR_TYPE_ERAT:
+			/*
+			 * Store the old slb content in paca before flushing.
+			 * Print this when we go to virtual mode.
+			 * There are chances that we may hit MCE again if there
+			 * is a parity error on the SLB entry we trying to read
+			 * for saving. Hence limit the slb saving to single
+			 * level of recursion.
+			 */
+			if (local_paca->in_mce == 1)
+				slb_save_contents(local_paca->mce_faulty_slbs);
+			flush_and_reload_slb();
+			disposition = RTAS_DISP_FULLY_RECOVERED;
+			break;
+		default:
+			break;
+		}
+	} else if (disposition == RTAS_DISP_LIMITED_RECOVERY) {
+		/* Platform corrected itself but could be degraded */
+		pr_err("MCE: limited recovery, system may be degraded\n");
+		disposition = RTAS_DISP_FULLY_RECOVERED;
+	}
+#endif
 out:
 	save_mce_event(regs, disposition == RTAS_DISP_FULLY_RECOVERED,
-		       &mce_err, regs->nip, eaddr, paddr);
-	return disposition;
-}
+			&mce_err, regs->nip, eaddr, paddr);
 
-static int mce_handle_error(struct pt_regs *regs, struct rtas_error_log *errp)
-{
-	struct pseries_errorlog *pseries_log;
-	struct pseries_mc_errorlog *mce_log = NULL;
-	int disposition = rtas_error_disposition(errp);
-	unsigned long msr;
-	u8 error_type;
-
-	if (!rtas_error_extended(errp))
-		goto out;
-
-	pseries_log = get_pseries_errorlog(errp, PSERIES_ELOG_SECT_ID_MCE);
-	if (!pseries_log)
-		goto out;
-
-	mce_log = (struct pseries_mc_errorlog *)pseries_log->data;
-	error_type = mce_log->error_type;
-
-	disposition = mce_handle_err_realmode(disposition, error_type);
-out:
-	disposition = mce_handle_err_virtmode(regs, errp, mce_log,
-					      disposition);
 	return disposition;
 }
 
-- 
2.31.1