From ce492b3b8f99cf9d2f807ec22d8805c996a09503 Mon Sep 17 00:00:00 2001 From: Stefan Agner Date: Fri, 3 Jun 2016 14:21:34 -0700 Subject: [PATCH] drm/fsl-dcu: use flat regmap cache Using flat regmap cache instead of RB-tree to avoid the following lockdep warning on driver load: WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:2755 lockdep_trace_alloc+0x15c/0x160() DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags)) The RB-tree regmap cache needs to allocate new space on first writes. However, allocations in an atomic context (e.g. when a spinlock is held) are not allowed. The function regmap_write calls map->lock, which acquires a spinlock in the fast_io case. Since the FSL DCU driver uses MMIO, the regmap bus of type regmap_mmio is being used which has fast_io set to true. Use flat regmap cache and specify max register to be large enouth to cover all registers available in LS1021a and Vybrids register space. Signed-off-by: Stefan Agner Cc: Mark Brown Cc: stable@vger.kernel.org --- drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c index 0ec1ad961e0d..dc723f7ead7d 100644 --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c @@ -42,9 +42,10 @@ static const struct regmap_config fsl_dcu_regmap_config = { .reg_bits = 32, .reg_stride = 4, .val_bits = 32, - .cache_type = REGCACHE_RBTREE, + .cache_type = REGCACHE_FLAT, .volatile_reg = fsl_dcu_drm_is_volatile_reg, + .max_register = 0x11fc, }; static int fsl_dcu_drm_irq_init(struct drm_device *dev) -- 2.20.1