From 602685e66f163f26179f41215cf302b0a894803e Mon Sep 17 00:00:00 2001 From: Antonio Borneo Date: Tue, 11 May 2010 11:35:28 +0800 Subject: [PATCH] NOR/CFI: add cfi_read() implementation Final step to force bus_width size during CFI flash read. Added CFI specific implementation cfi_read() that uses only accesses at bus_width size. Signed-off-by: Antonio Borneo --- src/flash/nor/cfi.c | 74 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 72 insertions(+), 2 deletions(-) diff --git a/src/flash/nor/cfi.c b/src/flash/nor/cfi.c index 1b080acd83..72c95dd1ab 100644 --- a/src/flash/nor/cfi.c +++ b/src/flash/nor/cfi.c @@ -4,6 +4,7 @@ * Copyright (C) 2009 Michael Schwingen * * michael@schwingen.org * * Copyright (C) 2010 Øyvind Harboe * + * Copyright (C) 2010 by Antonio Borneo * * * * This program is free software; you can redistribute it and/or modify * * it under the terms of the GNU General Public License as published by * @@ -1799,6 +1800,76 @@ static int cfi_write_words(struct flash_bank *bank, uint8_t *word, uint32_t word return ERROR_FLASH_OPERATION_FAILED; } +static int cfi_read(struct flash_bank *bank, uint8_t *buffer, uint32_t offset, uint32_t count) +{ + struct cfi_flash_bank *cfi_info = bank->driver_priv; + struct target *target = bank->target; + uint32_t address = bank->base + offset; + uint32_t read_p; + int align; /* number of unaligned bytes */ + uint8_t current_word[CFI_MAX_BUS_WIDTH]; + int i; + int retval; + + LOG_DEBUG("reading buffer of %i byte at 0x%8.8x", + (int)count, (unsigned)offset); + + if (bank->target->state != TARGET_HALTED) + { + LOG_ERROR("Target not halted"); + return ERROR_TARGET_NOT_HALTED; + } + + if (offset + count > bank->size) + return ERROR_FLASH_DST_OUT_OF_BANK; + + if (cfi_info->qry[0] != 'Q') + return ERROR_FLASH_BANK_NOT_PROBED; + + /* start at the first byte of the first word (bus_width size) */ + read_p = address & ~(bank->bus_width - 1); + if ((align = address - read_p) != 0) + { + LOG_INFO("Fixup %d unaligned read head bytes", align); + + /* read a complete word from flash */ + if ((retval = target_read_memory(target, read_p, bank->bus_width, 1, current_word)) != ERROR_OK) + return retval; + + /* take only bytes we need */ + for (i = align; (i < bank->bus_width) && (count > 0); i++, count--) + *buffer++ = current_word[i]; + + read_p += bank->bus_width; + } + + align = count / bank->bus_width; + if (align) + { + if ((retval = target_read_memory(target, read_p, bank->bus_width, align, buffer)) != ERROR_OK) + return retval; + + read_p += align * bank->bus_width; + buffer += align * bank->bus_width; + count -= align * bank->bus_width; + } + + if (count) + { + LOG_INFO("Fixup %d unaligned read tail bytes", count); + + /* read a complete word from flash */ + if ((retval = target_read_memory(target, read_p, bank->bus_width, 1, current_word)) != ERROR_OK) + return retval; + + /* take only bytes we need */ + for (i = 0; (i < bank->bus_width) && (count > 0); i++, count--) + *buffer++ = current_word[i]; + } + + return ERROR_OK; +} + static int cfi_write(struct flash_bank *bank, uint8_t *buffer, uint32_t offset, uint32_t count) { struct cfi_flash_bank *cfi_info = bank->driver_priv; @@ -2467,8 +2538,7 @@ struct flash_driver cfi_flash = { .erase = cfi_erase, .protect = cfi_protect, .write = cfi_write, - /* FIXME: access flash at bus_width size */ - .read = default_flash_read, + .read = cfi_read, .probe = cfi_probe, .auto_probe = cfi_auto_probe, /* FIXME: access flash at bus_width size */ -- 2.30.2