From a19b462f044b1bc5327f0bc871b46a03efb84363 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 4 Aug 2017 17:45:50 +0100 Subject: [PATCH] irqchip/gic-v3-its: Add post-mortem info on command timeout If the ITS stops processing commands, we're pretty much toasted as we cannot update the configuration anymore (and we're not even sure that the ITS still translates interrups). If that happens, let's dump some basic information about the state of affairs before moving on. Signed-off-by: Marc Zyngier --- 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 54ea4e26c7a9..0788de9a5407 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -690,9 +690,9 @@ static void its_flush_cmd(struct its_node *its, struct its_cmd_block *cmd) dsb(ishst); } -static void its_wait_for_range_completion(struct its_node *its, - struct its_cmd_block *from, - struct its_cmd_block *to) +static int its_wait_for_range_completion(struct its_node *its, + struct its_cmd_block *from, + struct its_cmd_block *to) { u64 rd_idx, from_idx, to_idx; u32 count = 1000000; /* 1s! */ @@ -713,12 +713,15 @@ static void its_wait_for_range_completion(struct its_node *its, count--; if (!count) { - pr_err_ratelimited("ITS queue timeout\n"); - return; + pr_err_ratelimited("ITS queue timeout (%llu %llu %llu)\n", + from_idx, to_idx, rd_idx); + return -1; } cpu_relax(); udelay(1); } + + return 0; } /* Warning, macro hell follows */ @@ -754,7 +757,8 @@ post: \ next_cmd = its_post_commands(its); \ raw_spin_unlock_irqrestore(&its->lock, flags); \ \ - its_wait_for_range_completion(its, cmd, next_cmd); \ + if (its_wait_for_range_completion(its, cmd, next_cmd)) \ + pr_err_ratelimited("ITS cmd %ps failed\n", builder); \ } static void its_build_sync_cmd(struct its_cmd_block *sync_cmd, -- 2.30.2