From: Meng Li Meng.Li@windriver.com

When an irq occurs in altera edac driver, regmap_xxx() 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.

Fixes mutex-lock error lock_acquire+0xfc/0x288 __mutex_lock+0x8c/0x808 mutex_lock_nested+0x3c/0x50 regmap_lock_mutex+0x24/0x30 regmap_write+0x40/0x78 a10_eccmgr_irq_unmask+0x34/0x40 unmask_irq.part.0+0x30/0x50 irq_enable+0x74/0x80 __irq_startup+0x80/0xa8 irq_startup+0x70/0x150 __setup_irq+0x650/0x6d0 request_threaded_irq+0xe4/0x180 devm_request_threaded_irq+0x7c/0xf0 altr_sdram_probe+0x2c4/0x600 <snip>

Upstream fix pending [1] (common code uses fast mode) [1] https://lkml.org/lkml/2019/11/7/1014

Fixes: 3dab6bd52687 ("EDAC, altera: Add support for Stratix10 SDRAM EDAC") Cc: stable@vger.kernel.org Reported-by: Meng Li Meng.Li@windriver.com Signed-off-by: Meng Li Meng.Li@windriver.com Reviewed-by: Thor Thayer thor.thayer@linux.intel.com --- v2 Change Author to Meng Li & Reviewed-by: Thor Thayer --- drivers/edac/altera_edac.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c index fbda4b876afd..0be3d1b17f03 100644 --- a/drivers/edac/altera_edac.c +++ b/drivers/edac/altera_edac.c @@ -560,6 +560,7 @@ static const struct regmap_config s10_sdram_regmap_cfg = { .reg_write = s10_protected_reg_write, .use_single_read = true, .use_single_write = true, + .fast_io = true, };

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