On 14/09/2023 14:40, Michael Tretter wrote:
> The IOMMU of the RGA is programmed with a list of DMA descriptors that
> contain an 32 bit address per 4k page in the video buffers. The address
> in the descriptor points to the start address of the page.
>
> Introduce 'struct rga_dma_desc' to make the handling of the DMA
> descriptors explicit instead of hiding them behind standard types.
>
> As the descriptors only handle 32 bit addresses, addresses above 4 GB
> cannot be addressed. If this is detected, stop filling the descriptor
> list and report an error.
>
> While at it, use provided helpers for iterating the sg_table instead of
> manually calculating the DMA addresses.
>
> Signed-off-by: Michael Tretter <m.tretter@xxxxxxxxxxxxxx>
> ---
> drivers/media/platform/rockchip/rga/rga-buf.c | 47 +++++++++++++++------------
> drivers/media/platform/rockchip/rga/rga.h | 8 +++--
> 2 files changed, 33 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/media/platform/rockchip/rga/rga-buf.c b/drivers/media/platform/rockchip/rga/rga-buf.c
> index 81508ed5abf3..df5ebc90e32d 100644
> --- a/drivers/media/platform/rockchip/rga/rga-buf.c
> +++ b/drivers/media/platform/rockchip/rga/rga-buf.c
> @@ -5,6 +5,7 @@
> */
>
> #include <linux/pm_runtime.h>
> +#include <linux/scatterlist.h>
>
> #include <media/v4l2-device.h>
> #include <media/v4l2-ioctl.h>
> @@ -15,6 +16,25 @@
> #include "rga-hw.h"
> #include "rga.h"
>
> +static int fill_descriptors(struct rga_dma_desc *desc, struct sg_table *sgt)
> +{
> + struct sg_dma_page_iter iter;
> + struct rga_dma_desc *tmp = desc;
> + unsigned int num_desc = 0;
> + dma_addr_t addr;
> +
> + for_each_sgtable_dma_page(sgt, &iter, 0) {
> + addr = sg_page_iter_dma_address(&iter);
> + if (upper_32_bits(addr) != 0L)
> + return -1;
> + tmp->addr = lower_32_bits(addr);
> + tmp++;
> + num_desc++;
> + }
> +
> + return num_desc;
> +}
> +
> static int
> rga_queue_setup(struct vb2_queue *vq,
> unsigned int *nbuffers, unsigned int *nplanes,
> @@ -114,11 +134,8 @@ void rga_buf_map(struct vb2_buffer *vb)
> {
> struct rga_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
> struct rockchip_rga *rga = ctx->rga;
> - struct sg_table *sgt;
> - struct scatterlist *sgl;
> - unsigned int *pages;
> - unsigned int address, len, i, p;
> - unsigned int mapped_size = 0;
> + struct rga_dma_desc *pages;
> + unsigned int num_desc = 0;
>
> if (vb->type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
> pages = rga->src_mmu_pages;
> @@ -126,23 +143,13 @@ void rga_buf_map(struct vb2_buffer *vb)
> pages = rga->dst_mmu_pages;
>
> /* Create local MMU table for RGA */
> - sgt = vb2_plane_cookie(vb, 0);
> -
> - for_each_sg(sgt->sgl, sgl, sgt->nents, i) {
> - len = sg_dma_len(sgl) >> PAGE_SHIFT;
> - address = sg_phys(sgl);
> -
> - for (p = 0; p < len; p++) {
> - dma_addr_t phys = address +
> - ((dma_addr_t)p << PAGE_SHIFT);
> -
> - pages[mapped_size + p] = phys;
> - }
> -
> - mapped_size += len;
> + num_desc = fill_descriptors(pages, vb2_dma_sg_plane_desc(vb, 0));
> + if (num_desc < 0) {
> + dev_err(rga->dev, "Failed to map buffer");
> + return;
> }
>
> /* sync local MMU table for RGA */
> dma_sync_single_for_device(rga->dev, virt_to_phys(pages),
> - 8 * PAGE_SIZE, DMA_BIDIRECTIONAL);
> + num_desc * sizeof(*pages), DMA_BIDIRECTIONAL);
> }
> diff --git a/drivers/media/platform/rockchip/rga/rga.h b/drivers/media/platform/rockchip/rga/rga.h
> index 5fa9d2f366dc..22f7da28ac51 100644
> --- a/drivers/media/platform/rockchip/rga/rga.h
> +++ b/drivers/media/platform/rockchip/rga/rga.h
> @@ -40,6 +40,10 @@ struct rga_frame {
> u32 size;
> };
>
> +struct rga_dma_desc {
> + u32 addr;
> +};
> +
> struct rockchip_rga_version {
> u32 major;
> u32 minor;
> @@ -81,8 +85,8 @@ struct rockchip_rga {
> struct rga_ctx *curr;
> dma_addr_t cmdbuf_phy;
> void *cmdbuf_virt;
> - unsigned int *src_mmu_pages;
> - unsigned int *dst_mmu_pages;
> + struct rga_dma_desc *src_mmu_pages;
> + struct rga_dma_desc *dst_mmu_pages;
This breaks compilation:
drivers/media/platform/rockchip/rga/rga.c: In function ‘rga_probe’:
drivers/media/platform/rockchip/rga/rga.c:875:28: error: assignment to ‘struct rga_dma_desc *’ from incompatible pointer type ‘unsigned int *’ [-Werror=incompatible-pointer-types]
875 | rga->src_mmu_pages =
| ^
drivers/media/platform/rockchip/rga/rga.c:881:28: error: assignment to ‘struct rga_dma_desc *’ from incompatible pointer type ‘unsigned int *’ [-Werror=incompatible-pointer-types]
881 | rga->dst_mmu_pages =
| ^
It's probably something that is fixed in a later patch, but as it is right
now this series breaks bisect.
Regards,
Hans
> };
>
> struct rga_frame *rga_get_frame(struct rga_ctx *ctx, enum v4l2_buf_type type);
>
