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author | Yann Sionneau <ysionneau@kalray.eu> | 2021-03-05 19:33:25 +0100 |
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committer | Sascha Hauer <s.hauer@pengutronix.de> | 2021-03-17 11:55:30 +0100 |
commit | 4808d6f80073da71b6eaf12cd31fa7dbee3a9d1a (patch) | |
tree | 0da2addaebe9bf6dd8110974747838e8b0e13ca8 /arch/kvx | |
parent | b329e641e71f438bfd338b20c30b0c810b671225 (diff) | |
download | barebox-4808d6f80073da71b6eaf12cd31fa7dbee3a9d1a.tar.gz barebox-4808d6f80073da71b6eaf12cd31fa7dbee3a9d1a.tar.xz |
kvx: Implement dma handling primitives
Signed-off-by: Jules Maselbas <jmaselbas@kalray.eu>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'arch/kvx')
-rw-r--r-- | arch/kvx/Kconfig | 1 | ||||
-rw-r--r-- | arch/kvx/include/asm/dma.h | 32 | ||||
-rw-r--r-- | arch/kvx/include/asm/sys_arch.h | 3 | ||||
-rw-r--r-- | arch/kvx/lib/Makefile | 2 | ||||
-rw-r--r-- | arch/kvx/lib/dma-default.c | 94 |
5 files changed, 131 insertions, 1 deletions
diff --git a/arch/kvx/Kconfig b/arch/kvx/Kconfig index 4e02613ec7..0934440880 100644 --- a/arch/kvx/Kconfig +++ b/arch/kvx/Kconfig @@ -13,6 +13,7 @@ config KVX select GENERIC_FIND_NEXT_BIT select HAS_ARCH_SJLJ select HAS_CACHE + select HAS_DMA select LIBFDT select MFD_SYSCON select OF_BAREBOX_DRIVERS diff --git a/arch/kvx/include/asm/dma.h b/arch/kvx/include/asm/dma.h new file mode 100644 index 0000000000..a7ecf279a9 --- /dev/null +++ b/arch/kvx/include/asm/dma.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* SPDX-FileCopyrightText: 2021 Yann Sionneau <ysionneau@kalray.eu>, Kalray Inc. */ + +#ifndef __ASM_DMA_H +#define __ASM_DMA_H + +#include <common.h> + +#define KVX_DDR_32BIT_RAM_WINDOW_BA (0x80000000ULL) +#define KVX_DDR_64BIT_RAM_WINDOW_BA (0x100000000ULL) +#define MAX_32BIT_ADDR (0xffffffffULL) + +#define dma_alloc dma_alloc +static inline void *dma_alloc(size_t size) +{ + return xmemalign(64, ALIGN(size, 64)); +} + +static inline void *dma_alloc_coherent(size_t size, dma_addr_t *dma_handle) +{ + BUILD_BUG_ON_MSG(1, "dma_alloc_coherent not supported: " + "MMU support is required to map uncached pages"); + return NULL; +} + +static inline void dma_free_coherent(void *mem, dma_addr_t dma_handle, + size_t size) +{ + free(mem); +} + +#endif /* __ASM_DMA_H */ diff --git a/arch/kvx/include/asm/sys_arch.h b/arch/kvx/include/asm/sys_arch.h index 9df32c4e72..ce07a55986 100644 --- a/arch/kvx/include/asm/sys_arch.h +++ b/arch/kvx/include/asm/sys_arch.h @@ -11,6 +11,9 @@ #define EXCEPTION_STRIDE 0x40 #define EXCEPTION_ALIGNMENT 0x100 +#define kvx_cluster_id() ((int) \ + ((kvx_sfr_get(PCR) & KVX_SFR_PCR_CID_MASK) \ + >> KVX_SFR_PCR_CID_SHIFT)) #define KVX_SFR_START(__sfr_reg) \ (KVX_SFR_## __sfr_reg ## _SHIFT) diff --git a/arch/kvx/lib/Makefile b/arch/kvx/lib/Makefile index d271ebccfa..c730e1c23f 100644 --- a/arch/kvx/lib/Makefile +++ b/arch/kvx/lib/Makefile @@ -3,4 +3,4 @@ # Copyright (C) 2019 Kalray Inc. # -obj-y += cpuinfo.o board.o dtb.o poweroff.o bootm.o setjmp.o cache.o +obj-y += cpuinfo.o board.o dtb.o poweroff.o bootm.o setjmp.o cache.o dma-default.o diff --git a/arch/kvx/lib/dma-default.c b/arch/kvx/lib/dma-default.c new file mode 100644 index 0000000000..2a4144696c --- /dev/null +++ b/arch/kvx/lib/dma-default.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0-only +// SPDX-FileCopyrightText: 2021 Yann Sionneau <ysionneau@kalray.eu>, Kalray Inc. + +#include <dma.h> +#include <asm/barrier.h> +#include <asm/io.h> +#include <asm/cache.h> +#include <asm/sfr.h> +#include <asm/sys_arch.h> + +/* + * The implementation of arch should follow the following rules: + * map for_cpu for_device unmap + * TO_DEV writeback none writeback none + * FROM_DEV invalidate invalidate(*) invalidate invalidate(*) + * BIDIR writeback invalidate writeback invalidate + * + * (*) - only necessary if the CPU speculatively prefetches. + * + * (see https://lkml.org/lkml/2018/5/18/979) + */ + +void dma_sync_single_for_device(dma_addr_t addr, size_t size, + enum dma_data_direction dir) +{ + /* dcache is Write-Through: no need to flush to force writeback */ + switch (dir) { + case DMA_FROM_DEVICE: + invalidate_dcache_range(addr, addr + size); + break; + case DMA_TO_DEVICE: + case DMA_BIDIRECTIONAL: + /* allow device to read buffer written by CPU */ + wmb(); + break; + default: + BUG(); + } +} + +void dma_sync_single_for_cpu(dma_addr_t addr, size_t size, + enum dma_data_direction dir) +{ + /* CPU does not speculatively prefetches */ + switch (dir) { + case DMA_FROM_DEVICE: + /* invalidate has been done during map/for_device */ + case DMA_TO_DEVICE: + break; + case DMA_BIDIRECTIONAL: + invalidate_dcache_range(addr, addr + size); + break; + default: + BUG(); + } +} + +#define KVX_DDR_ALIAS_OFFSET \ + (KVX_DDR_64BIT_RAM_WINDOW_BA - KVX_DDR_32BIT_RAM_WINDOW_BA) +#define KVX_DDR_ALIAS_WINDOW \ + (KVX_DDR_64BIT_RAM_WINDOW_BA + KVX_DDR_ALIAS_OFFSET) + +/* Local smem is aliased between 0 and 16MB */ +#define KVX_SMEM_LOCAL_ALIAS 0x1000000ULL + +dma_addr_t dma_map_single(struct device_d *dev, void *ptr, size_t size, + enum dma_data_direction dir) +{ + uintptr_t addr = (uintptr_t) ptr; + + dma_sync_single_for_device(addr, size, dir); + + /* Local smem alias should never be used for dma */ + if (addr < KVX_SMEM_LOCAL_ALIAS) + return addr + (1 + kvx_cluster_id()) * KVX_SMEM_LOCAL_ALIAS; + + if (dev->dma_mask && addr <= dev->dma_mask) + return addr; + + if (addr >= KVX_DDR_ALIAS_WINDOW) + return DMA_ERROR_CODE; + + addr -= KVX_DDR_ALIAS_OFFSET; + if (dev->dma_mask && addr > dev->dma_mask) + return DMA_ERROR_CODE; + + return addr; +} + +void dma_unmap_single(struct device_d *dev, dma_addr_t addr, size_t size, + enum dma_data_direction dir) +{ + dma_sync_single_for_cpu(addr, size, dir); +} |