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authorMd Sadre Alam <quic_mdalam@quicinc.com>2024-12-20 15:12:03 +0530
committerVinod Koul <vkoul@kernel.org>2024-12-24 15:06:40 +0530
commit57a7138d0627309d469719f1845d2778c251f358 (patch)
tree4e3457052a328a0148615f6d0f0fc094bbbad76d /drivers/dma
parent308213731f8cc772245adb729ae2364fb1d20e98 (diff)
dmaengine: qcom: bam_dma: Avoid writing unavailable register
Avoid writing unavailable register in BAM-Lite mode. BAM_DESC_CNT_TRSHLD register is unavailable in BAM-Lite mode. Its only available in BAM-NDP mode. So only write this register for clients who is using BAM-NDP. Signed-off-by: Md Sadre Alam <quic_mdalam@quicinc.com> Link: https://lore.kernel.org/r/20241220094203.3510335-1-quic_mdalam@quicinc.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
-rw-r--r--drivers/dma/qcom/bam_dma.c24
1 files changed, 16 insertions, 8 deletions
diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index bbc3276992bb..c14557efd577 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -59,6 +59,9 @@ struct bam_desc_hw {
#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;
@@ -398,6 +401,7 @@ struct bam_device {
/* dma start transaction tasklet */
struct tasklet_struct task;
+ u32 bam_revision;
};
/**
@@ -441,8 +445,10 @@ static void bam_reset(struct bam_device *bdev)
writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
/* set descriptor threshold, start with 4 bytes */
- writel_relaxed(DEFAULT_CNT_THRSHLD,
- bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD));
+ 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));
/* 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));
@@ -1000,9 +1006,10 @@ static void bam_apply_new_config(struct bam_chan *bchan,
maxburst = bchan->slave.src_maxburst;
else
maxburst = bchan->slave.dst_maxburst;
-
- writel_relaxed(maxburst,
- bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD));
+ 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));
}
bchan->reconfigure = 0;
@@ -1192,10 +1199,11 @@ static int bam_init(struct bam_device *bdev)
u32 val;
/* read revision and configuration information */
- if (!bdev->num_ees) {
- val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION));
+ val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION));
+ if (!bdev->num_ees)
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)