[irqchip: irq/irqchip-fixes] irqchip/gic-v3: Fix GICR_CTLR.RWP polling

From: irqchip-bot for Marc Zyngier
Date: Tue Apr 05 2022 - 16:17:42 EST


The following commit has been merged into the irq/irqchip-fixes branch of irqchip:

Commit-ID: 0df6664531a12cdd8fc873f0cac0dcb40243d3e9
Gitweb: https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms/0df6664531a12cdd8fc873f0cac0dcb40243d3e9
Author: Marc Zyngier <maz@xxxxxxxxxx>
AuthorDate: Tue, 15 Mar 2022 16:50:32
Committer: Marc Zyngier <maz@xxxxxxxxxx>
CommitterDate: Tue, 05 Apr 2022 16:33:13 +01:00

irqchip/gic-v3: Fix GICR_CTLR.RWP polling

It turns out that our polling of RWP is totally wrong when checking
for it in the redistributors, as we test the *distributor* bit index,
whereas it is a different bit number in the RDs... Oopsie boo.

This is embarassing. Not only because it is wrong, but also because
it took *8 years* to notice the blunder...

Just fix the damn thing.

Fixes: 021f653791ad ("irqchip: gic-v3: Initial support for GICv3")
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Andre Przywara <andre.przywara@xxxxxxx>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Link: https://lore.kernel.org/r/20220315165034.794482-2-maz@xxxxxxxxxx
---
drivers/irqchip/irq-gic-v3.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 0efe1a9..9b63165 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -206,11 +206,11 @@ static inline void __iomem *gic_dist_base(struct irq_data *d)
}
}

-static void gic_do_wait_for_rwp(void __iomem *base)
+static void gic_do_wait_for_rwp(void __iomem *base, u32 bit)
{
u32 count = 1000000; /* 1s! */

- while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) {
+ while (readl_relaxed(base + GICD_CTLR) & bit) {
count--;
if (!count) {
pr_err_ratelimited("RWP timeout, gone fishing\n");
@@ -224,13 +224,13 @@ static void gic_do_wait_for_rwp(void __iomem *base)
/* Wait for completion of a distributor change */
static void gic_dist_wait_for_rwp(void)
{
- gic_do_wait_for_rwp(gic_data.dist_base);
+ gic_do_wait_for_rwp(gic_data.dist_base, GICD_CTLR_RWP);
}

/* Wait for completion of a redistributor change */
static void gic_redist_wait_for_rwp(void)
{
- gic_do_wait_for_rwp(gic_data_rdist_rd_base());
+ gic_do_wait_for_rwp(gic_data_rdist_rd_base(), GICR_CTLR_RWP);
}

#ifdef CONFIG_ARM64