From 62e8b851783138a11da63285be0fbf69530ff73d Mon Sep 17 00:00:00 2001 From: Ezequiel Garcia Date: Fri, 4 Oct 2013 15:30:38 -0300 Subject: [PATCH] mtd: nand: pxa3xx: Allocate data buffer on detected flash size This commit replaces the currently hardcoded buffer size, by a dynamic detection scheme. First a small 256 bytes buffer is allocated so the device can be detected (using READID and friends commands). After detection, this buffer is released and a new buffer is allocated to acommodate the page size plus out-of-band size. Signed-off-by: Ezequiel Garcia Tested-by: Daniel Mack Signed-off-by: Brian Norris --- drivers/mtd/nand/pxa3xx_nand.c | 45 ++++++++++++++++++++++------------ 1 file changed, 30 insertions(+), 15 deletions(-) diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c index 287997487b95..64c258ec0170 100644 --- a/drivers/mtd/nand/pxa3xx_nand.c +++ b/drivers/mtd/nand/pxa3xx_nand.c @@ -39,6 +39,13 @@ #define NAND_STOP_DELAY (2 * HZ/50) #define PAGE_CHUNK_SIZE (2048) +/* + * Define a buffer size for the initial command that detects the flash device: + * STATUS, READID and PARAM. The largest of these is the PARAM command, + * needing 256 bytes. + */ +#define INIT_BUFFER_SIZE 256 + /* registers and bit definitions */ #define NDCR (0x00) /* Control register */ #define NDTR0CS0 (0x04) /* Timing Parameter 0 for CS0 */ @@ -164,6 +171,7 @@ struct pxa3xx_nand_info { unsigned int buf_start; unsigned int buf_count; + unsigned int buf_size; /* DMA information */ int drcmr_dat; @@ -911,26 +919,20 @@ static int pxa3xx_nand_detect_config(struct pxa3xx_nand_info *info) return 0; } -/* the maximum possible buffer size for large page with OOB data - * is: 2048 + 64 = 2112 bytes, allocate a page here for both the - * data buffer and the DMA descriptor - */ -#define MAX_BUFF_SIZE PAGE_SIZE - #ifdef ARCH_HAS_DMA static int pxa3xx_nand_init_buff(struct pxa3xx_nand_info *info) { struct platform_device *pdev = info->pdev; - int data_desc_offset = MAX_BUFF_SIZE - sizeof(struct pxa_dma_desc); + int data_desc_offset = info->buf_size - sizeof(struct pxa_dma_desc); if (use_dma == 0) { - info->data_buff = kmalloc(MAX_BUFF_SIZE, GFP_KERNEL); + info->data_buff = kmalloc(info->buf_size, GFP_KERNEL); if (info->data_buff == NULL) return -ENOMEM; return 0; } - info->data_buff = dma_alloc_coherent(&pdev->dev, MAX_BUFF_SIZE, + info->data_buff = dma_alloc_coherent(&pdev->dev, info->buf_size, &info->data_buff_phys, GFP_KERNEL); if (info->data_buff == NULL) { dev_err(&pdev->dev, "failed to allocate dma buffer\n"); @@ -944,7 +946,7 @@ static int pxa3xx_nand_init_buff(struct pxa3xx_nand_info *info) pxa3xx_nand_data_dma_irq, info); if (info->data_dma_ch < 0) { dev_err(&pdev->dev, "failed to request data dma\n"); - dma_free_coherent(&pdev->dev, MAX_BUFF_SIZE, + dma_free_coherent(&pdev->dev, info->buf_size, info->data_buff, info->data_buff_phys); return info->data_dma_ch; } @@ -962,7 +964,7 @@ static void pxa3xx_nand_free_buff(struct pxa3xx_nand_info *info) struct platform_device *pdev = info->pdev; if (use_dma) { pxa_free_dma(info->data_dma_ch); - dma_free_coherent(&pdev->dev, MAX_BUFF_SIZE, + dma_free_coherent(&pdev->dev, info->buf_size, info->data_buff, info->data_buff_phys); } else { kfree(info->data_buff); @@ -971,7 +973,7 @@ static void pxa3xx_nand_free_buff(struct pxa3xx_nand_info *info) #else static int pxa3xx_nand_init_buff(struct pxa3xx_nand_info *info) { - info->data_buff = kmalloc(MAX_BUFF_SIZE, GFP_KERNEL); + info->data_buff = kmalloc(info->buf_size, GFP_KERNEL); if (info->data_buff == NULL) return -ENOMEM; return 0; @@ -1085,7 +1087,16 @@ KEEP_CONFIG: else host->col_addr_cycles = 1; + /* release the initial buffer */ + kfree(info->data_buff); + + /* allocate the real data + oob buffer */ + info->buf_size = mtd->writesize + mtd->oobsize; + ret = pxa3xx_nand_init_buff(info); + if (ret) + return ret; info->oob_buff = info->data_buff + mtd->writesize; + if ((mtd->size >> chip->page_shift) > 65536) host->row_addr_cycles = 3; else @@ -1191,9 +1202,13 @@ static int alloc_nand_resource(struct platform_device *pdev) } info->mmio_phys = r->start; - ret = pxa3xx_nand_init_buff(info); - if (ret) + /* Allocate a buffer to allow flash detection */ + info->buf_size = INIT_BUFFER_SIZE; + info->data_buff = kmalloc(info->buf_size, GFP_KERNEL); + if (info->data_buff == NULL) { + ret = -ENOMEM; goto fail_disable_clk; + } /* initialize all interrupts to be disabled */ disable_int(info, NDSR_MASK); @@ -1211,7 +1226,7 @@ static int alloc_nand_resource(struct platform_device *pdev) fail_free_buf: free_irq(irq, info); - pxa3xx_nand_free_buff(info); + kfree(info->data_buff); fail_disable_clk: clk_disable_unprepare(info->clk); return ret;