On Fri, Jan 30, 2026 at 04:31:45PM +0530, Sai Sree Kartheek Adivi wrote:
> Relocate the ring management functions such as push, pop, and reset
> from k3-udma.c to k3-udma-common.c file. These operations are
> common across multiple K3 UDMA variants and will be reused by
> future implementations like K3 UDMA v2.
>
> No functional changes intended.
>
> Signed-off-by: Sai Sree Kartheek Adivi <s-adivi@ti.com>
> ---
Reviewed-by: Frank Li <Frank.Li@nxp.com>
> drivers/dma/ti/k3-udma-common.c | 103 ++++++++++++++++++++++++++++++++
> drivers/dma/ti/k3-udma.c | 100 -------------------------------
> drivers/dma/ti/k3-udma.h | 4 ++
> 3 files changed, 107 insertions(+), 100 deletions(-)
>
> diff --git a/drivers/dma/ti/k3-udma-common.c b/drivers/dma/ti/k3-udma-common.c
> index 9cb35759c70bb..4dcf986f84d87 100644
> --- a/drivers/dma/ti/k3-udma-common.c
> +++ b/drivers/dma/ti/k3-udma-common.c
> @@ -1239,5 +1239,108 @@ void udma_desc_pre_callback(struct virt_dma_chan *vc,
> }
> EXPORT_SYMBOL_GPL(udma_desc_pre_callback);
>
> +int udma_push_to_ring(struct udma_chan *uc, int idx)
> +{
> + struct udma_desc *d = uc->desc;
> + struct k3_ring *ring = NULL;
> + dma_addr_t paddr;
> +
> + switch (uc->config.dir) {
> + case DMA_DEV_TO_MEM:
> + ring = uc->rflow->fd_ring;
> + break;
> + case DMA_MEM_TO_DEV:
> + case DMA_MEM_TO_MEM:
> + ring = uc->tchan->t_ring;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + /* RX flush packet: idx == -1 is only passed in case of DEV_TO_MEM */
> + if (idx == -1) {
> + paddr = udma_get_rx_flush_hwdesc_paddr(uc);
> + } else {
> + paddr = udma_curr_cppi5_desc_paddr(d, idx);
> +
> + wmb(); /* Ensure that writes are not moved over this point */
> + }
> +
> + return k3_ringacc_ring_push(ring, &paddr);
> +}
> +EXPORT_SYMBOL_GPL(udma_push_to_ring);
> +
> +int udma_pop_from_ring(struct udma_chan *uc, dma_addr_t *addr)
> +{
> + struct k3_ring *ring = NULL;
> + int ret;
> +
> + switch (uc->config.dir) {
> + case DMA_DEV_TO_MEM:
> + ring = uc->rflow->r_ring;
> + break;
> + case DMA_MEM_TO_DEV:
> + case DMA_MEM_TO_MEM:
> + ring = uc->tchan->tc_ring;
> + break;
> + default:
> + return -ENOENT;
> + }
> +
> + ret = k3_ringacc_ring_pop(ring, addr);
> + if (ret)
> + return ret;
> +
> + rmb(); /* Ensure that reads are not moved before this point */
> +
> + /* Teardown completion */
> + if (cppi5_desc_is_tdcm(*addr))
> + return 0;
> +
> + /* Check for flush descriptor */
> + if (udma_desc_is_rx_flush(uc, *addr))
> + return -ENOENT;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(udma_pop_from_ring);
> +
> +void udma_reset_rings(struct udma_chan *uc)
> +{
> + struct k3_ring *ring1 = NULL;
> + struct k3_ring *ring2 = NULL;
> +
> + switch (uc->config.dir) {
> + case DMA_DEV_TO_MEM:
> + if (uc->rchan) {
> + ring1 = uc->rflow->fd_ring;
> + ring2 = uc->rflow->r_ring;
> + }
> + break;
> + case DMA_MEM_TO_DEV:
> + case DMA_MEM_TO_MEM:
> + if (uc->tchan) {
> + ring1 = uc->tchan->t_ring;
> + ring2 = uc->tchan->tc_ring;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + if (ring1)
> + k3_ringacc_ring_reset_dma(ring1,
> + k3_ringacc_ring_get_occ(ring1));
> + if (ring2)
> + k3_ringacc_ring_reset(ring2);
> +
> + /* make sure we are not leaking memory by stalled descriptor */
> + if (uc->terminated_desc) {
> + udma_desc_free(&uc->terminated_desc->vd);
> + uc->terminated_desc = NULL;
> + }
> +}
> +EXPORT_SYMBOL_GPL(udma_reset_rings);
> +
> MODULE_DESCRIPTION("Texas Instruments K3 UDMA Common Library");
> MODULE_LICENSE("GPL v2");
> diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
> index 0a1291829611f..214a1ca1e1776 100644
> --- a/drivers/dma/ti/k3-udma.c
> +++ b/drivers/dma/ti/k3-udma.c
> @@ -174,106 +174,6 @@ static bool udma_is_chan_paused(struct udma_chan *uc)
> return false;
> }
>
> -static int udma_push_to_ring(struct udma_chan *uc, int idx)
> -{
> - struct udma_desc *d = uc->desc;
> - struct k3_ring *ring = NULL;
> - dma_addr_t paddr;
> -
> - switch (uc->config.dir) {
> - case DMA_DEV_TO_MEM:
> - ring = uc->rflow->fd_ring;
> - break;
> - case DMA_MEM_TO_DEV:
> - case DMA_MEM_TO_MEM:
> - ring = uc->tchan->t_ring;
> - break;
> - default:
> - return -EINVAL;
> - }
> -
> - /* RX flush packet: idx == -1 is only passed in case of DEV_TO_MEM */
> - if (idx == -1) {
> - paddr = udma_get_rx_flush_hwdesc_paddr(uc);
> - } else {
> - paddr = udma_curr_cppi5_desc_paddr(d, idx);
> -
> - wmb(); /* Ensure that writes are not moved over this point */
> - }
> -
> - return k3_ringacc_ring_push(ring, &paddr);
> -}
> -
> -static int udma_pop_from_ring(struct udma_chan *uc, dma_addr_t *addr)
> -{
> - struct k3_ring *ring = NULL;
> - int ret;
> -
> - switch (uc->config.dir) {
> - case DMA_DEV_TO_MEM:
> - ring = uc->rflow->r_ring;
> - break;
> - case DMA_MEM_TO_DEV:
> - case DMA_MEM_TO_MEM:
> - ring = uc->tchan->tc_ring;
> - break;
> - default:
> - return -ENOENT;
> - }
> -
> - ret = k3_ringacc_ring_pop(ring, addr);
> - if (ret)
> - return ret;
> -
> - rmb(); /* Ensure that reads are not moved before this point */
> -
> - /* Teardown completion */
> - if (cppi5_desc_is_tdcm(*addr))
> - return 0;
> -
> - /* Check for flush descriptor */
> - if (udma_desc_is_rx_flush(uc, *addr))
> - return -ENOENT;
> -
> - return 0;
> -}
> -
> -static void udma_reset_rings(struct udma_chan *uc)
> -{
> - struct k3_ring *ring1 = NULL;
> - struct k3_ring *ring2 = NULL;
> -
> - switch (uc->config.dir) {
> - case DMA_DEV_TO_MEM:
> - if (uc->rchan) {
> - ring1 = uc->rflow->fd_ring;
> - ring2 = uc->rflow->r_ring;
> - }
> - break;
> - case DMA_MEM_TO_DEV:
> - case DMA_MEM_TO_MEM:
> - if (uc->tchan) {
> - ring1 = uc->tchan->t_ring;
> - ring2 = uc->tchan->tc_ring;
> - }
> - break;
> - default:
> - break;
> - }
> -
> - if (ring1)
> - k3_ringacc_ring_reset_dma(ring1,
> - k3_ringacc_ring_get_occ(ring1));
> - if (ring2)
> - k3_ringacc_ring_reset(ring2);
> -
> - /* make sure we are not leaking memory by stalled descriptor */
> - if (uc->terminated_desc) {
> - udma_desc_free(&uc->terminated_desc->vd);
> - uc->terminated_desc = NULL;
> - }
> -}
> -
> static void udma_decrement_byte_counters(struct udma_chan *uc, u32 val)
> {
> if (uc->desc->dir == DMA_DEV_TO_MEM) {
> diff --git a/drivers/dma/ti/k3-udma.h b/drivers/dma/ti/k3-udma.h
> index 7c807bd9e178b..4c6e5b946d5cf 100644
> --- a/drivers/dma/ti/k3-udma.h
> +++ b/drivers/dma/ti/k3-udma.h
> @@ -610,6 +610,10 @@ void udma_desc_pre_callback(struct virt_dma_chan *vc,
> struct virt_dma_desc *vd,
> struct dmaengine_result *result);
>
> +int udma_push_to_ring(struct udma_chan *uc, int idx);
> +int udma_pop_from_ring(struct udma_chan *uc, dma_addr_t *addr);
> +void udma_reset_rings(struct udma_chan *uc);
> +
> /* Direct access to UDMA low lever resources for the glue layer */
> int xudma_navss_psil_pair(struct udma_dev *ud, u32 src_thread, u32 dst_thread);
> int xudma_navss_psil_unpair(struct udma_dev *ud, u32 src_thread,
> --
> 2.34.1
>