From d7f25f35f448b15f815d355abd9ba39836fd9e32 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 27 Feb 2014 13:26:03 -0700 Subject: [PATCH] cros_ec: Add a function for decoding the Chrome OS EC flashmap In order to talk to the EC properly we need to be able to understand the layout of its internal flash memory. This permits emulation of the EC for sandbox, and also software update in a system with a real EC. Signed-off-by: Simon Glass --- drivers/misc/cros_ec.c | 50 ++++++++++++++++++++++++++++++++++++++++++ include/cros_ec.h | 19 ++++++++++++++++ 2 files changed, 69 insertions(+) diff --git a/drivers/misc/cros_ec.c b/drivers/misc/cros_ec.c index 301e8ebbf5..1998653754 100644 --- a/drivers/misc/cros_ec.c +++ b/drivers/misc/cros_ec.c @@ -958,6 +958,56 @@ int cros_ec_decode_region(int argc, char * const argv[]) return -1; } +int cros_ec_decode_ec_flash(const void *blob, struct fdt_cros_ec *config) +{ + int flash_node, node; + + node = fdtdec_next_compatible(blob, 0, COMPAT_GOOGLE_CROS_EC); + if (node < 0) { + debug("Failed to find chrome-ec node'\n"); + return -1; + } + + flash_node = fdt_subnode_offset(blob, node, "flash"); + if (flash_node < 0) { + debug("Failed to find flash node\n"); + return -1; + } + + if (fdtdec_read_fmap_entry(blob, flash_node, "flash", + &config->flash)) { + debug("Failed to decode flash node in chrome-ec'\n"); + return -1; + } + + config->flash_erase_value = fdtdec_get_int(blob, flash_node, + "erase-value", -1); + for (node = fdt_first_subnode(blob, flash_node); node >= 0; + node = fdt_next_subnode(blob, node)) { + const char *name = fdt_get_name(blob, node, NULL); + enum ec_flash_region region; + + if (0 == strcmp(name, "ro")) { + region = EC_FLASH_REGION_RO; + } else if (0 == strcmp(name, "rw")) { + region = EC_FLASH_REGION_RW; + } else if (0 == strcmp(name, "wp-ro")) { + region = EC_FLASH_REGION_WP_RO; + } else { + debug("Unknown EC flash region name '%s'\n", name); + return -1; + } + + if (fdtdec_read_fmap_entry(blob, node, "reg", + &config->region[region])) { + debug("Failed to decode flash region in chrome-ec'\n"); + return -1; + } + } + + return 0; +} + /** * Perform a flash read or write command * diff --git a/include/cros_ec.h b/include/cros_ec.h index 22eae90605..999c3c90c5 100644 --- a/include/cros_ec.h +++ b/include/cros_ec.h @@ -63,6 +63,17 @@ struct mbkp_keyscan { uint8_t data[CROS_EC_KEYSCAN_COLS]; }; +/* Holds information about the Chrome EC */ +struct fdt_cros_ec { + struct fmap_entry flash; /* Address and size of EC flash */ + /* + * Byte value of erased flash, or -1 if not known. It is normally + * 0xff but some flash devices use 0 (e.g. STM32Lxxx) + */ + int flash_erase_value; + struct fmap_entry region[EC_FLASH_REGION_COUNT]; +}; + /** * Read the ID of the CROS-EC device * @@ -449,4 +460,12 @@ int cros_ec_board_init(void); */ int cros_ec_get_error(void); +/** + * Returns information from the FDT about the Chrome EC flash + * + * @param blob FDT blob to use + * @param config Structure to use to return information + */ +int cros_ec_decode_ec_flash(const void *blob, struct fdt_cros_ec *config); + #endif -- 2.39.2