From 47c298f792992c6eda26fc4e4630c7ca54dcec47 Mon Sep 17 00:00:00 2001 From: Lucas Stach Date: Wed, 3 May 2017 10:38:18 +0200 Subject: [PATCH] gpu: ipu-v3: pre: only use internal clock gating By setting the SFTRST bit, the PRE will be held in the lowest power state with clocks to the internal blocks gated. When external clock gating is used (from the external clock controller, or by setting the CLKGATE bit) the PRE will sporadically fail to start. Signed-off-by: Lucas Stach Fixes: d2a34232580a ("gpu: ipu-v3: add driver for Prefetch Resolve Engine") Signed-off-by: Philipp Zabel --- drivers/gpu/ipu-v3/ipu-pre.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/ipu-v3/ipu-pre.c b/drivers/gpu/ipu-v3/ipu-pre.c index c55563379e2e..c35f74c83065 100644 --- a/drivers/gpu/ipu-v3/ipu-pre.c +++ b/drivers/gpu/ipu-v3/ipu-pre.c @@ -131,8 +131,6 @@ int ipu_pre_get(struct ipu_pre *pre) if (pre->in_use) return -EBUSY; - clk_prepare_enable(pre->clk_axi); - /* first get the engine out of reset and remove clock gating */ writel(0, pre->regs + IPU_PRE_CTRL); @@ -149,12 +147,7 @@ int ipu_pre_get(struct ipu_pre *pre) void ipu_pre_put(struct ipu_pre *pre) { - u32 val; - - val = IPU_PRE_CTRL_SFTRST | IPU_PRE_CTRL_CLKGATE; - writel(val, pre->regs + IPU_PRE_CTRL); - - clk_disable_unprepare(pre->clk_axi); + writel(IPU_PRE_CTRL_SFTRST, pre->regs + IPU_PRE_CTRL); pre->in_use = false; } @@ -249,6 +242,8 @@ static int ipu_pre_probe(struct platform_device *pdev) if (!pre->buffer_virt) return -ENOMEM; + clk_prepare_enable(pre->clk_axi); + pre->dev = dev; platform_set_drvdata(pdev, pre); mutex_lock(&ipu_pre_list_mutex); @@ -268,6 +263,8 @@ static int ipu_pre_remove(struct platform_device *pdev) available_pres--; mutex_unlock(&ipu_pre_list_mutex); + clk_disable_unprepare(pre->clk_axi); + if (pre->buffer_virt) gen_pool_free(pre->iram, (unsigned long)pre->buffer_virt, IPU_PRE_MAX_WIDTH * IPU_PRE_NUM_SCANLINES * 4); -- 2.30.2