[PATCH v5 4/6] riscv: mm: dma-noncoherent: Pass direction and operation to ALT_CMO_OP()

Prabhakar
2022-12-12T11:55:50Z

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Pass direction and operation to ALT_CMO_OP() macro.

Vendors might want to perform different operations based on the direction
and callbacks (arch_sync_dma_for_device/arch_sync_dma_for_cpu/
arch_dma_prep_coherent) so to handle such cases pass the direction and
operation to ALT_CMO_OP() macro. This is in preparation for adding errata
for the Andes CPU core.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
v4 -> v5
* Updated commit message.

RFC v3 -> v4
* New patch
---
arch/riscv/include/asm/cacheflush.h | 4 ++++
arch/riscv/include/asm/errata_list.h | 8 ++++++--
arch/riscv/mm/dma-noncoherent.c | 15 ++++++++++-----
3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h
index 03e3b95ae6da..e22019668b9e 100644
--- a/arch/riscv/include/asm/cacheflush.h
+++ b/arch/riscv/include/asm/cacheflush.h
@@ -8,6 +8,10 @@

#include <linux/mm.h>

+#define NON_COHERENT_SYNC_DMA_FOR_DEVICE 0
+#define NON_COHERENT_SYNC_DMA_FOR_CPU 1
+#define NON_COHERENT_DMA_PREP 2
+
static inline void local_flush_icache_all(void)
{
asm volatile ("fence.i" ::: "memory");
diff --git a/arch/riscv/include/asm/errata_list.h b/arch/riscv/include/asm/errata_list.h
index 2ba7e6e74540..48e899a8e7a9 100644
--- a/arch/riscv/include/asm/errata_list.h
+++ b/arch/riscv/include/asm/errata_list.h
@@ -124,7 +124,7 @@ asm volatile(ALTERNATIVE( \
#define THEAD_flush_A0 ".long 0x0275000b"
#define THEAD_SYNC_S ".long 0x0190000b"

-#define ALT_CMO_OP(_op, _start, _size, _cachesize) \
+#define ALT_CMO_OP(_op, _start, _size, _cachesize, _dir, _ops) \
asm volatile(ALTERNATIVE_2( \
__nops(6), \
"mv a0, %1\n\t" \
@@ -146,7 +146,11 @@ asm volatile(ALTERNATIVE_2( \
ERRATA_THEAD_CMO, CONFIG_ERRATA_THEAD_CMO) \
: : "r"(_cachesize), \
"r"((unsigned long)(_start) & ~((_cachesize) - 1UL)), \
- "r"((unsigned long)(_start) + (_size)) \
+ "r"((unsigned long)(_start) + (_size)), \
+ "r"((unsigned long)(_start)), \
+ "r"((unsigned long)(_size)), \
+ "r"((unsigned long)(_dir)), \
+ "r"((unsigned long)(_ops)) \
: "a0")

#define THEAD_C9XX_RV_IRQ_PMU 17
diff --git a/arch/riscv/mm/dma-noncoherent.c b/arch/riscv/mm/dma-noncoherent.c
index d919efab6eba..e2b82034f504 100644
--- a/arch/riscv/mm/dma-noncoherent.c
+++ b/arch/riscv/mm/dma-noncoherent.c
@@ -19,13 +19,16 @@ void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,

switch (dir) {
case DMA_TO_DEVICE:
- ALT_CMO_OP(clean, vaddr, size, riscv_cbom_block_size);
+ ALT_CMO_OP(clean, vaddr, size, riscv_cbom_block_size,
+ dir, NON_COHERENT_SYNC_DMA_FOR_DEVICE);
break;
case DMA_FROM_DEVICE:
- ALT_CMO_OP(clean, vaddr, size, riscv_cbom_block_size);
+ ALT_CMO_OP(clean, vaddr, size, riscv_cbom_block_size,
+ dir, NON_COHERENT_SYNC_DMA_FOR_DEVICE);
break;
case DMA_BIDIRECTIONAL:
- ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size);
+ ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size,
+ dir, NON_COHERENT_SYNC_DMA_FOR_DEVICE);
break;
default:
break;
@@ -42,7 +45,8 @@ void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
break;
case DMA_FROM_DEVICE:
case DMA_BIDIRECTIONAL:
- ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size);
+ ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size,
+ dir, NON_COHERENT_SYNC_DMA_FOR_CPU);
break;
default:
break;
@@ -53,7 +57,8 @@ 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);
+ ALT_CMO_OP(flush, flush_addr, size, riscv_cbom_block_size,
+ 0, NON_COHERENT_DMA_PREP);
}

void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
--
2.25.1