Hi Tomasz: On Fri, 2019-07-05 at 13:22 +0900, Tomasz Figa wrote: > Hi Jungo, > > On Fri, Jul 5, 2019 at 12:33 PM Jungo Lin <jungo....@mediatek.com> wrote: > > > > Hi Tomasz,
[snip] > > After applying your suggestion in SCP device driver, we could remove > > mtk_cam-smem.h/c. Currently, we use dma_alloc_coherent with SCP device > > to get SCP address. We could touch the buffer with this SCP address in > > SCP processor. > > > > After that, we use dma_map_page_attrs with P1 device which supports > > IOMMU domain to get IOVA address. For this address, we will assign > > it to our ISP HW device to proceed. > > > > Below is the snippet for ISP P1 compose buffer initialization. > > > > ptr = dma_alloc_coherent(p1_dev->cam_dev.smem_dev, > > MAX_COMPOSER_SIZE, &addr, GFP_KERNEL); > > if (!ptr) { > > dev_err(dev, "failed to allocate compose memory\n"); > > return -ENOMEM; > > } > > isp_ctx->scp_mem_pa = addr; > > addr contains a DMA address, not a physical address. Could we call it > scp_mem_dma instead? > > > dev_dbg(dev, "scp addr:%pad\n", &addr); > > > > /* get iova address */ > > addr = dma_map_page_attrs(dev, phys_to_page(addr), 0, > > addr is a DMA address, so phys_to_page() can't be called on it. The > simplest thing here would be to use dma_map_single() with ptr as the > CPU address expected. > We have changed to use ma_map_single() with ptr, but encounter IOMMU error. From the debug log of iommu_dma_map_page[3], we got 0x0000000054800000 instead of expected address: 0x0000000050800000[2]. There is a address offset(0x4000000). If we change to use dma_map_page_attrs with phys_to_page(addr), the address is correct as we expected[2]. Do you have any suggestion on this issue? Do we miss something? [1] [ 1.344786] __dma_alloc_from_coherent: 0x800000 PAGE_SHIFT:12 device_base:0x0000000050000000 dma:0x0000000050800000 virt_base:ffffff8014000000 va:ffffff8014800000 [ 1.346890] mtk-cam 1a000000.camisp: scp addr:0x0000000050800000 va:ffffff8014800000 [ 1.347864] iommu_dma_map_page:0x0000000054800000 offset:0 [ 1.348562] mtk-cam 1a000000.camisp: iova addr:0x00000000fde00000 [2] [ 1.346738] __dma_alloc_from_coherent: 0x800000 PAGE_SHIFT:12 device_base:0x0000000050000000 dma:0x0000000050800000 virt_base:ffffff8014000000 va:ffffff8014800000 [ 1.348841] mtk-cam 1a000000.camisp: scp addr:0x0000000050800000 va:ffffff8014800000 [ 1.349816] iommu_dma_map_page:0x0000000050800000 offset:0 [ 1.350514] mtk-cam 1a000000.camisp: iova addr:0x00000000fde00000 [3] dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, int prot) { phys_addr_t phys = page_to_phys(page); pr_err("iommu_dma_map_page:%pa offset:%lu\n", &phys, offset); return __iommu_dma_map(dev, page_to_phys(page) + offset, size, prot, iommu_get_dma_domain(dev)); } [snip] Best regards, Jungo