[PATCH 5.3 042/180] EDAC/altera: Use fast register IO for S10 IRQs

Greg Kroah-Hartman
2019-12-16T18:34:49Z

From: Meng Li <Meng.Li@windriver.com>

commit 56d9e7bd3fa0f105b6670021d167744bc50ae4fe upstream.

When an IRQ occurs, regmap_{read,write,...}() is invoked in atomic
context. Regmap must indicate register IO is fast so that a spinlock is
used instead of a mutex to avoid sleeping in atomic context:

lock_acquire
__mutex_lock
mutex_lock_nested
regmap_lock_mutex
regmap_write
a10_eccmgr_irq_unmask
unmask_irq.part.0
irq_enable
__irq_startup
irq_startup
__setup_irq
request_threaded_irq
devm_request_threaded_irq
altr_sdram_probe

Mark it so.

[ bp: Massage. ]

Fixes: 3dab6bd52687 ("EDAC, altera: Add support for Stratix10 SDRAM EDAC")
Reported-by: Meng Li <Meng.Li@windriver.com>
Signed-off-by: Meng Li <Meng.Li@windriver.com>
Signed-off-by: Thor Thayer <thor.thayer@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: James Morse <james.morse@arm.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Robert Richter <rrichter@marvell.com>
Cc: stable <stable@vger.kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/1574361048-17572-2-git-send-email-thor.thayer@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/edac/altera_edac.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -561,6 +561,7 @@ static const struct regmap_config s10_sd
.reg_write = s10_protected_reg_write,
.use_single_read = true,
.use_single_write = true,
+ .fast_io = true,
};

/************** </Stratix10 EDAC Memory Controller Functions> ***********/