diff options
Diffstat (limited to 'drivers/mtd/devices')
| -rw-r--r-- | drivers/mtd/devices/phram.c | 15 | ||||
| -rw-r--r-- | drivers/mtd/devices/spear_smi.c | 38 |
2 files changed, 46 insertions, 7 deletions
diff --git a/drivers/mtd/devices/phram.c b/drivers/mtd/devices/phram.c index 8b66e52ca3cc..9734e6903fe6 100644 --- a/drivers/mtd/devices/phram.c +++ b/drivers/mtd/devices/phram.c @@ -247,22 +247,25 @@ static int phram_setup(const char *val) ret = parse_num64(&start, token[1]); if (ret) { - kfree(name); parse_err("illegal start address\n"); + goto error; } ret = parse_num64(&len, token[2]); if (ret) { - kfree(name); parse_err("illegal device length\n"); + goto error; } ret = register_device(name, start, len); - if (!ret) - pr_info("%s device: %#llx at %#llx\n", name, len, start); - else - kfree(name); + if (ret) + goto error; + + pr_info("%s device: %#llx at %#llx\n", name, len, start); + return 0; +error: + kfree(name); return ret; } diff --git a/drivers/mtd/devices/spear_smi.c b/drivers/mtd/devices/spear_smi.c index dd5069876537..4a7da5fde714 100644 --- a/drivers/mtd/devices/spear_smi.c +++ b/drivers/mtd/devices/spear_smi.c @@ -595,6 +595,26 @@ static int spear_mtd_read(struct mtd_info *mtd, loff_t from, size_t len, return 0; } +/* + * The purpose of this function is to ensure a memcpy_toio() with byte writes + * only. Its structure is inspired from the ARM implementation of _memcpy_toio() + * which also does single byte writes but cannot be used here as this is just an + * implementation detail and not part of the API. Not mentioning the comment + * stating that _memcpy_toio() should be optimized. + */ +static void spear_smi_memcpy_toio_b(volatile void __iomem *dest, + const void *src, size_t len) +{ + const unsigned char *from = src; + + while (len) { + len--; + writeb(*from, dest); + from++; + dest++; + } +} + static inline int spear_smi_cpy_toio(struct spear_smi *dev, u32 bank, void __iomem *dest, const void *src, size_t len) { @@ -617,7 +637,23 @@ static inline int spear_smi_cpy_toio(struct spear_smi *dev, u32 bank, ctrlreg1 = readl(dev->io_base + SMI_CR1); writel((ctrlreg1 | WB_MODE) & ~SW_MODE, dev->io_base + SMI_CR1); - memcpy_toio(dest, src, len); + /* + * In Write Burst mode (WB_MODE), the specs states that writes must be: + * - incremental + * - of the same size + * The ARM implementation of memcpy_toio() will optimize the number of + * I/O by using as much 4-byte writes as possible, surrounded by + * 2-byte/1-byte access if: + * - the destination is not 4-byte aligned + * - the length is not a multiple of 4-byte. + * Avoid this alternance of write access size by using our own 'byte + * access' helper if at least one of the two conditions above is true. + */ + if (IS_ALIGNED(len, sizeof(u32)) && + IS_ALIGNED((uintptr_t)dest, sizeof(u32))) + memcpy_toio(dest, src, len); + else + spear_smi_memcpy_toio_b(dest, src, len); writel(ctrlreg1, dev->io_base + SMI_CR1); |