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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/riscv/mm/dma-noncoherent.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/riscv/mm/dma-noncoherent.c')
-rw-r--r--arch/riscv/mm/dma-noncoherent.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/riscv/mm/dma-noncoherent.c b/arch/riscv/mm/dma-noncoherent.c
new file mode 100644
index 000000000..d919efab6
--- /dev/null
+++ b/arch/riscv/mm/dma-noncoherent.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * RISC-V specific functions to support DMA for non-coherent devices
+ *
+ * Copyright (c) 2021 Western Digital Corporation or its affiliates.
+ */
+
+#include <linux/dma-direct.h>
+#include <linux/dma-map-ops.h>
+#include <linux/mm.h>
+#include <asm/cacheflush.h>
+
+static bool noncoherent_supported;
+
+void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
+ enum dma_data_direction dir)
+{
+ void *vaddr = phys_to_virt(paddr);
+
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ ALT_CMO_OP(clean, vaddr, size, riscv_cbom_block_size);
+ break;
+ case DMA_FROM_DEVICE:
+ ALT_CMO_OP(clean, vaddr, size, riscv_cbom_block_size);
+ break;
+ case DMA_BIDIRECTIONAL:
+ ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size);
+ break;
+ default:
+ break;
+ }
+}
+
+void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
+ enum dma_data_direction dir)
+{
+ void *vaddr = phys_to_virt(paddr);
+
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ break;
+ case DMA_FROM_DEVICE:
+ case DMA_BIDIRECTIONAL:
+ ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size);
+ break;
+ default:
+ break;
+ }
+}
+
+void arch_dma_prep_coherent(struct page *page, size_t size)
+{
+ void *flush_addr = page_address(page);
+
+ ALT_CMO_OP(flush, flush_addr, size, riscv_cbom_block_size);
+}
+
+void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+ const struct iommu_ops *iommu, bool coherent)
+{
+ WARN_TAINT(!coherent && riscv_cbom_block_size > ARCH_DMA_MINALIGN,
+ TAINT_CPU_OUT_OF_SPEC,
+ "%s %s: ARCH_DMA_MINALIGN smaller than riscv,cbom-block-size (%d < %d)",
+ dev_driver_string(dev), dev_name(dev),
+ ARCH_DMA_MINALIGN, riscv_cbom_block_size);
+
+ WARN_TAINT(!coherent && !noncoherent_supported, TAINT_CPU_OUT_OF_SPEC,
+ "%s %s: device non-coherent but no non-coherent operations supported",
+ dev_driver_string(dev), dev_name(dev));
+
+ dev->dma_coherent = coherent;
+}
+
+void riscv_noncoherent_supported(void)
+{
+ WARN(!riscv_cbom_block_size,
+ "Non-coherent DMA support enabled without a block size\n");
+ noncoherent_supported = true;
+}