From 1a7adfda349e9211b816928eecd5246e44f2f74d Mon Sep 17 00:00:00 2001 From: Tomi Valkeinen Date: Mon, 14 Jun 2021 13:23:29 +0200 Subject: [PATCH] media: ti-vpe: cal: add cal_ctx_wr_dma_enable and fix a race I have not noticed any errors due to this, but the DMA configuration looks racy. Setting the DMA mode bitfield in CAL_WR_DMA_CTRL supposedly enables the DMA. However, the driver currently a) continues configuring the DMA after setting the mode, and b) enables the DMA interrupts only after setting the mode. This probably doesn't cause any issues as there should be no data coming in to the DMA yet, but it's still better to fix this. Add a new function, cal_ctx_wr_dma_enable(), to set the DMA mode field, and call that function only after the DMA config and the irq enabling has been done. Signed-off-by: Tomi Valkeinen Reviewed-by: Laurent Pinchart Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/platform/ti-vpe/cal.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/media/platform/ti-vpe/cal.c b/drivers/media/platform/ti-vpe/cal.c index fdfa5ad..cd8ec04 100644 --- a/drivers/media/platform/ti-vpe/cal.c +++ b/drivers/media/platform/ti-vpe/cal.c @@ -409,8 +409,6 @@ static void cal_ctx_wr_dma_config(struct cal_ctx *ctx) CAL_WR_DMA_CTRL_YSIZE_MASK); cal_set_field(&val, CAL_WR_DMA_CTRL_DTAG_PIX_DAT, CAL_WR_DMA_CTRL_DTAG_MASK); - cal_set_field(&val, CAL_WR_DMA_CTRL_MODE_CONST, - CAL_WR_DMA_CTRL_MODE_MASK); cal_set_field(&val, CAL_WR_DMA_CTRL_PATTERN_LINEAR, CAL_WR_DMA_CTRL_PATTERN_MASK); cal_set_field(&val, 1, CAL_WR_DMA_CTRL_STALL_RD_MASK); @@ -442,6 +440,15 @@ void cal_ctx_set_dma_addr(struct cal_ctx *ctx, dma_addr_t addr) cal_write(ctx->cal, CAL_WR_DMA_ADDR(ctx->dma_ctx), addr); } +static void cal_ctx_wr_dma_enable(struct cal_ctx *ctx) +{ + u32 val = cal_read(ctx->cal, CAL_WR_DMA_CTRL(ctx->dma_ctx)); + + cal_set_field(&val, CAL_WR_DMA_CTRL_MODE_CONST, + CAL_WR_DMA_CTRL_MODE_MASK); + cal_write(ctx->cal, CAL_WR_DMA_CTRL(ctx->dma_ctx), val); +} + static void cal_ctx_wr_dma_disable(struct cal_ctx *ctx) { u32 val = cal_read(ctx->cal, CAL_WR_DMA_CTRL(ctx->dma_ctx)); @@ -500,6 +507,8 @@ void cal_ctx_start(struct cal_ctx *ctx) CAL_HL_IRQ_WDMA_END_MASK(ctx->dma_ctx)); cal_write(ctx->cal, CAL_HL_IRQENABLE_SET(2), CAL_HL_IRQ_WDMA_START_MASK(ctx->dma_ctx)); + + cal_ctx_wr_dma_enable(ctx); } void cal_ctx_stop(struct cal_ctx *ctx) -- 2.7.4