From dbacf38b4227ffcd9a7eafdb49d395208229286c Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Wed, 13 May 2015 13:10:32 -0700 Subject: [PATCH 110/203] mailbox/bcm2835: Fix mailbox full detection. With the VC reader blocked and the ARM writing, MAIL0_STA reads empty permanently while MAIL1_STA goes from empty (0x40000000) to non-empty (0x00000001-0x00000007) to full (0x80000008). This bug ended up having no effect on us, because all of our transactions in the client driver were synchronous and under a mutex. Suggested-by: Phil Elwell Signed-off-by: Eric Anholt Acked-by: Stephen Warren Signed-off-by: Jassi Brar --- drivers/mailbox/bcm2835-mailbox.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/mailbox/bcm2835-mailbox.c +++ b/drivers/mailbox/bcm2835-mailbox.c @@ -49,6 +49,7 @@ #define MAIL0_STA (ARM_0_MAIL0 + 0x18) #define MAIL0_CNF (ARM_0_MAIL0 + 0x1C) #define MAIL1_WRT (ARM_0_MAIL1 + 0x00) +#define MAIL1_STA (ARM_0_MAIL1 + 0x18) /* Status register: FIFO state. */ #define ARM_MS_FULL BIT(31) @@ -117,7 +118,7 @@ static bool bcm2835_last_tx_done(struct bool ret; spin_lock(&mbox->lock); - ret = !(readl(mbox->regs + MAIL0_STA) & ARM_MS_FULL); + ret = !(readl(mbox->regs + MAIL1_STA) & ARM_MS_FULL); spin_unlock(&mbox->lock); return ret; }