| | 1 | /* |
| | 2 | * mach-davinci/sram.c - DaVinci simple SRAM allocator |
| | 3 | * |
| | 4 | * Copyright (C) 2009 David Brownell |
| | 5 | * |
| | 6 | * This program is free software; you can redistribute it and/or modify |
| | 7 | * it under the terms of the GNU General Public License as published by |
| | 8 | * the Free Software Foundation; either version 2 of the License, or |
| | 9 | * (at your option) any later version. |
| | 10 | */ |
| | 11 | #include <linux/module.h> |
| | 12 | #include <linux/init.h> |
| | 13 | #include <linux/io.h> |
| | 14 | #include <linux/genalloc.h> |
| | 15 | |
| | 16 | #include <mach/common.h> |
| | 17 | #include <mach/sram.h> |
| | 18 | |
| | 19 | static struct gen_pool *sram_pool; |
| | 20 | |
| | 21 | struct gen_pool *sram_get_gen_pool(void) |
| | 22 | { |
| | 23 | return sram_pool; |
| | 24 | } |
| | 25 | |
| | 26 | void *sram_alloc(size_t len, dma_addr_t *dma) |
| | 27 | { |
| | 28 | dma_addr_t dma_base = davinci_soc_info.sram_dma; |
| | 29 | |
| | 30 | if (dma) |
| | 31 | *dma = 0; |
| | 32 | if (!sram_pool || (dma && !dma_base)) |
| | 33 | return NULL; |
| | 34 | |
| | 35 | return gen_pool_dma_alloc(sram_pool, len, dma); |
| | 36 | |
| | 37 | } |
| | 38 | EXPORT_SYMBOL(sram_alloc); |
| | 39 | |
| | 40 | void sram_free(void *addr, size_t len) |
| | 41 | { |
| | 42 | gen_pool_free(sram_pool, (unsigned long) addr, len); |
| | 43 | } |
| | 44 | EXPORT_SYMBOL(sram_free); |
| | 45 | |
| | 46 | |
| | 47 | /* |
| | 48 | * REVISIT This supports CPU and DMA access to/from SRAM, but it |
| | 49 | * doesn't (yet?) support some other notable uses of SRAM: as TCM |
| | 50 | * for data and/or instructions; and holding code needed to enter |
| | 51 | * and exit suspend states (while DRAM can't be used). |
| | 52 | */ |
| | 53 | static int __init sram_init(void) |
| | 54 | { |
| | 55 | phys_addr_t phys = davinci_soc_info.sram_dma; |
| | 56 | unsigned len = davinci_soc_info.sram_len; |
| | 57 | int status = 0; |
| | 58 | void __iomem *addr; |
| | 59 | |
| | 60 | if (len) { |
| | 61 | len = min_t(unsigned, len, SRAM_SIZE); |
| | 62 | sram_pool = gen_pool_create(ilog2(SRAM_GRANULARITY), -1); |
| | 63 | if (!sram_pool) |
| | 64 | status = -ENOMEM; |
| | 65 | } |
| | 66 | |
| | 67 | if (sram_pool) { |
| | 68 | addr = ioremap(phys, len); |
| | 69 | if (!addr) |
| | 70 | return -ENOMEM; |
| | 71 | status = gen_pool_add_virt(sram_pool, (unsigned long) addr, |
| | 72 | phys, len, -1); |
| | 73 | if (status < 0) |
| | 74 | iounmap(addr); |
| | 75 | } |
| | 76 | |
| | 77 | WARN_ON(status < 0); |
| | 78 | return status; |
| | 79 | } |
| | 80 | core_initcall(sram_init); |
| | 81 | |
projects / linux-2.6-block.git / blame_incremental