On 12/9/2024 1:01 PM, Md Sadre Alam wrote:
> 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@xxxxxxxxxxx>
> ---
>
> Change in [v3]
>
> * Removed BAM_LITE macro
>
> * Updated commit message
>
> * Adjusted if condition check
>
> * Renamed BAM-NDP macro to BAM_NDP_REVISION_START and
> BAM_NDP_REVISION_END
>
> Change in [v2]
>
> * Replace 0xff with REVISION_MASK in the statement
> bdev->bam_revision = val & REVISION_MASK
>
> Change in [v1]
>
> * Added initial patch
>
> drivers/dma/qcom/bam_dma.c | 24 ++++++++++++++++--------
> 1 file changed, 16 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
> index d43a881e43b9..a00dd0331ff5 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 (bdev->bam_revision >= BAM_NDP_REVISION_START &&
> + bdev->bam_revision <= BAM_NDP_REVISION_END)
Please use in_range().
> + 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 (bdev->bam_revision >= BAM_NDP_REVISION_START &&
> + bdev->bam_revision <= BAM_NDP_REVISION_END)
Please use in_range().
Thanks & Regards,
Manikanta.
