6.6-stable review patch. If anyone has any objections, please let me know.
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From: Fang Xiang fangxiang3@xiaomi.com
[ Upstream commit d3badb15613c14dd35d3495b1dde5c90fcd616dd ]
In non-coherent GIC designs, the ITS tables must be flushed before writing to the GITS_BASER<n> registers, otherwise the ITS could read dirty tables, which results in unpredictable behavior.
Flush the tables right at the begin of its_setup_baser() to prevent that.
[ tglx: Massage changelog ]
Fixes: a8707f553884 ("irqchip/gic-v3: Add Rockchip 3588001 erratum workaround") Suggested-by: Marc Zyngier maz@kernel.org Signed-off-by: Fang Xiang fangxiang3@xiaomi.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20231030083256.4345-1-fangxiang3@xiaomi.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/irqchip/irq-gic-v3-its.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index a8c89df1a9978..9a7a74239eabb 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -2379,12 +2379,12 @@ static int its_setup_baser(struct its_node *its, struct its_baser *baser, break; }
+ if (!shr) + gic_flush_dcache_to_poc(base, PAGE_ORDER_TO_SIZE(order)); + its_write_baser(its, baser, val); tmp = baser->val;
- if (its->flags & ITS_FLAGS_FORCE_NON_SHAREABLE) - tmp &= ~GITS_BASER_SHAREABILITY_MASK; - if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) { /* * Shareability didn't stick. Just use @@ -2394,10 +2394,9 @@ static int its_setup_baser(struct its_node *its, struct its_baser *baser, * non-cacheable as well. */ shr = tmp & GITS_BASER_SHAREABILITY_MASK; - if (!shr) { + if (!shr) cache = GITS_BASER_nC; - gic_flush_dcache_to_poc(base, PAGE_ORDER_TO_SIZE(order)); - } + goto retry_baser; }
@@ -2609,6 +2608,11 @@ static int its_alloc_tables(struct its_node *its) /* erratum 24313: ignore memory access type */ cache = GITS_BASER_nCnB;
+ if (its->flags & ITS_FLAGS_FORCE_NON_SHAREABLE) { + cache = GITS_BASER_nC; + shr = 0; + } + for (i = 0; i < GITS_BASER_NR_REGS; i++) { struct its_baser *baser = its->tables + i; u64 val = its_read_baser(its, baser);