[PATCH] Revert "dmaengine: qcom: bam_dma: Avoid writing unavailable register"
From: Caleb Connolly <hidden>
Date: 2025-02-08 22:31:18
Also in:
linux-arm-msm
Subsystem:
arm/qualcomm mailing list, dma generic offload engine subsystem, the rest · Maintainers:
Vinod Koul, Linus Torvalds
This commit causes a hard crash on sdm845 and likely other platforms. Revert it until a proper fix is found. This reverts commit 57a7138d0627309d469719f1845d2778c251f358. Signed-off-by: Caleb Connolly <redacted> --- drivers/dma/qcom/bam_dma.c | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-)
diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index c14557efd577..bbc3276992bb 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c@@ -58,11 +58,8 @@ struct bam_desc_hw { #define DESC_FLAG_EOB BIT(13) #define DESC_FLAG_NWD BIT(12) #define DESC_FLAG_CMD BIT(11) -#define BAM_NDP_REVISION_START 0x20 -#define BAM_NDP_REVISION_END 0x27 - struct bam_async_desc { struct virt_dma_desc vd; u32 num_desc;
@@ -400,9 +397,8 @@ struct bam_device { int irq; /* dma start transaction tasklet */ struct tasklet_struct task; - u32 bam_revision; }; /** * bam_addr - returns BAM register address
@@ -444,12 +440,10 @@ static void bam_reset(struct bam_device *bdev) val |= BAM_EN; writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL)); /* set descriptor threshold, start with 4 bytes */ - if (in_range(bdev->bam_revision, BAM_NDP_REVISION_START, - BAM_NDP_REVISION_END)) - writel_relaxed(DEFAULT_CNT_THRSHLD, - bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); + writel_relaxed(DEFAULT_CNT_THRSHLD, + bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); /* Enable default set of h/w workarounds, ie all except BAM_FULL_PIPE */ writel_relaxed(BAM_CNFG_BITS_DEFAULT, bam_addr(bdev, 0, BAM_CNFG_BITS));
@@ -1005,12 +999,11 @@ static void bam_apply_new_config(struct bam_chan *bchan, if (dir == DMA_DEV_TO_MEM) maxburst = bchan->slave.src_maxburst; else maxburst = bchan->slave.dst_maxburst; - if (in_range(bdev->bam_revision, BAM_NDP_REVISION_START, - BAM_NDP_REVISION_END)) - writel_relaxed(maxburst, - bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); + + writel_relaxed(maxburst, + bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); } bchan->reconfigure = 0; }
@@ -1198,13 +1191,12 @@ static int bam_init(struct bam_device *bdev) { u32 val; /* read revision and configuration information */ - val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION)); - if (!bdev->num_ees) + if (!bdev->num_ees) { + val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION)); bdev->num_ees = (val >> NUM_EES_SHIFT) & NUM_EES_MASK; - - bdev->bam_revision = val & REVISION_MASK; + } /* check that configured EE is within range */ if (bdev->ee >= bdev->num_ees) return -EINVAL;
--
2.48.1