From 282498d65fb4740c2e9212a79c6888887d0be6cf Mon Sep 17 00:00:00 2001
From: Cédric Le Goater <clg@kaod.org>
Date: Tue, 8 May 2018 09:05:17 +0200
Subject: [PATCH] powerpc/xive: prepare all hcalls to support long busy delays

References: bsc#1088273
Patch-mainline: v4.18-rc1
Git-commit: 282498d65fb4740c2e9212a79c6888887d0be6cf

This is not the case for the moment, but future releases of pHyp might
need to introduce some synchronisation routines under the hood which
would make the XIVE hcalls longer to complete.

As this was done for H_INT_RESET, let's wrap the other hcalls in a
loop catching the H_LONG_BUSY_* codes.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 arch/powerpc/sysdev/xive/spapr.c | 36 ++++++++++++++++++++++++++++--------
 1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c
index 864de3a733c7..575db3b06a6b 100644
--- a/arch/powerpc/sysdev/xive/spapr.c
+++ b/arch/powerpc/sysdev/xive/spapr.c
@@ -164,7 +164,10 @@ static long plpar_int_get_source_info(unsigned long flags,
 	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
 	long rc;
 
-	rc = plpar_hcall(H_INT_GET_SOURCE_INFO, retbuf, flags, lisn);
+	do {
+		rc = plpar_hcall(H_INT_GET_SOURCE_INFO, retbuf, flags, lisn);
+	} while (plpar_busy_delay(rc));
+
 	if (rc) {
 		pr_err("H_INT_GET_SOURCE_INFO lisn=%ld failed %ld\n", lisn, rc);
 		return rc;
@@ -197,8 +200,11 @@ static long plpar_int_set_source_config(unsigned long flags,
 		flags, lisn, target, prio, sw_irq);
 
 
-	rc = plpar_hcall_norets(H_INT_SET_SOURCE_CONFIG, flags, lisn,
-				target, prio, sw_irq);
+	do {
+		rc = plpar_hcall_norets(H_INT_SET_SOURCE_CONFIG, flags, lisn,
+					target, prio, sw_irq);
+	} while (plpar_busy_delay(rc));
+
 	if (rc) {
 		pr_err("H_INT_SET_SOURCE_CONFIG lisn=%ld target=%lx prio=%lx failed %ld\n",
 		       lisn, target, prio, rc);
@@ -217,7 +223,11 @@ static long plpar_int_get_queue_info(unsigned long flags,
 	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
 	long rc;
 
-	rc = plpar_hcall(H_INT_GET_QUEUE_INFO, retbuf, flags, target, priority);
+	do {
+		rc = plpar_hcall(H_INT_GET_QUEUE_INFO, retbuf, flags, target,
+				 priority);
+	} while (plpar_busy_delay(rc));
+
 	if (rc) {
 		pr_err("H_INT_GET_QUEUE_INFO cpu=%ld prio=%ld failed %ld\n",
 		       target, priority, rc);
@@ -246,8 +256,11 @@ static long plpar_int_set_queue_config(unsigned long flags,
 	pr_devel("H_INT_SET_QUEUE_CONFIG flags=%lx target=%lx priority=%lx qpage=%lx qsize=%lx\n",
 		flags,  target, priority, qpage, qsize);
 
-	rc = plpar_hcall_norets(H_INT_SET_QUEUE_CONFIG, flags, target,
-				priority, qpage, qsize);
+	do {
+		rc = plpar_hcall_norets(H_INT_SET_QUEUE_CONFIG, flags, target,
+					priority, qpage, qsize);
+	} while (plpar_busy_delay(rc));
+
 	if (rc) {
 		pr_err("H_INT_SET_QUEUE_CONFIG cpu=%ld prio=%ld qpage=%lx returned %ld\n",
 		       target, priority, qpage, rc);
@@ -261,7 +274,10 @@ static long plpar_int_sync(unsigned long flags, unsigned long lisn)
 {
 	long rc;
 
-	rc = plpar_hcall_norets(H_INT_SYNC, flags, lisn);
+	do {
+		rc = plpar_hcall_norets(H_INT_SYNC, flags, lisn);
+	} while (plpar_busy_delay(rc));
+
 	if (rc) {
 		pr_err("H_INT_SYNC lisn=%ld returned %ld\n", lisn, rc);
 		return  rc;
@@ -284,7 +300,11 @@ static long plpar_int_esb(unsigned long flags,
 	pr_devel("H_INT_ESB flags=%lx lisn=%lx offset=%lx in=%lx\n",
 		flags,  lisn, offset, in_data);
 
-	rc = plpar_hcall(H_INT_ESB, retbuf, flags, lisn, offset, in_data);
+	do {
+		rc = plpar_hcall(H_INT_ESB, retbuf, flags, lisn, offset,
+				 in_data);
+	} while (plpar_busy_delay(rc));
+
 	if (rc) {
 		pr_err("H_INT_ESB lisn=%ld offset=%ld returned %ld\n",
 		       lisn, offset, rc);
-- 
2.13.6