1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. 3 4 #include <linux/cache.h> 5 #include <linux/dma-map-ops.h> 6 #include <linux/genalloc.h> 7 #include <linux/highmem.h> 8 #include <linux/io.h> 9 #include <linux/mm.h> 10 #include <linux/scatterlist.h> 11 #include <linux/types.h> 12 #include <asm/cache.h> 13 14 static inline void cache_op(phys_addr_t paddr, size_t size, 15 void (*fn)(unsigned long start, unsigned long end)) 16 { 17 struct page *page = phys_to_page(paddr); 18 void *start = __va(page_to_phys(page)); 19 unsigned long offset = offset_in_page(paddr); 20 size_t left = size; 21 22 do { 23 size_t len = left; 24 25 if (offset + len > PAGE_SIZE) 26 len = PAGE_SIZE - offset; 27 28 if (PageHighMem(page)) { 29 start = kmap_atomic(page); 30 31 fn((unsigned long)start + offset, 32 (unsigned long)start + offset + len); 33 34 kunmap_atomic(start); 35 } else { 36 fn((unsigned long)start + offset, 37 (unsigned long)start + offset + len); 38 } 39 offset = 0; 40 41 page++; 42 start += PAGE_SIZE; 43 left -= len; 44 } while (left); 45 } 46 47 static void dma_wbinv_set_zero_range(unsigned long start, unsigned long end) 48 { 49 memset((void *)start, 0, end - start); 50 dma_wbinv_range(start, end); 51 } 52 53 void arch_dma_prep_coherent(struct page *page, size_t size) 54 { 55 cache_op(page_to_phys(page), size, dma_wbinv_set_zero_range); 56 } 57 58 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, 59 enum dma_data_direction dir) 60 { 61 switch (dir) { 62 case DMA_TO_DEVICE: 63 cache_op(paddr, size, dma_wb_range); 64 break; 65 case DMA_FROM_DEVICE: 66 case DMA_BIDIRECTIONAL: 67 cache_op(paddr, size, dma_wbinv_range); 68 break; 69 default: 70 BUG(); 71 } 72 } 73 74 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, 75 enum dma_data_direction dir) 76 { 77 switch (dir) { 78 case DMA_TO_DEVICE: 79 return; 80 case DMA_FROM_DEVICE: 81 case DMA_BIDIRECTIONAL: 82 cache_op(paddr, size, dma_inv_range); 83 break; 84 default: 85 BUG(); 86 } 87 } 88