diff options
| -rw-r--r-- | spi.c | 23 |
1 files changed, 22 insertions, 1 deletions
@@ -22,6 +22,7 @@ * Contains the generic SPI framework */ +#include <string.h> #include "flash.h" #include "flashchips.h" #include "chipdrivers.h" @@ -207,6 +208,7 @@ int default_spi_send_multicommand(struct spi_command *cmds) int spi_chip_read(struct flashchip *flash, uint8_t *buf, int start, int len) { + int addrbase = 0; if (!spi_programmer[spi_controller].read) { msg_perr("%s called, but SPI read is unsupported on this " "hardware. Please report a bug at " @@ -214,7 +216,26 @@ int spi_chip_read(struct flashchip *flash, uint8_t *buf, int start, int len) return 1; } - return spi_programmer[spi_controller].read(flash, buf, start, len); + /* Check if the chip fits between lowest valid and highest possible + * address. Highest possible address with the current SPI implementation + * means 0xffffff, the highest unsigned 24bit number. + */ + addrbase = spi_get_valid_read_addr(); + if (addrbase + flash->total_size * 1024 > (1 << 24)) { + msg_perr("Flash chip size exceeds the allowed access window. "); + msg_perr("Read will probably fail.\n"); + /* Try to get the best alignment subject to constraints. */ + addrbase = (1 << 24) - flash->total_size * 1024; + } + /* Check if alignment is native (at least the largest power of two which + * is a factor of the mapped size of the chip). + */ + if (ffs(flash->total_size * 1024) > (ffs(addrbase) ? : 33)) { + msg_perr("Flash chip is not aligned natively in the allowed " + "access window.\n"); + msg_perr("Read will probably return garbage.\n"); + } + return spi_programmer[spi_controller].read(flash, buf, addrbase + start, len); } /* |