diff options
Diffstat (limited to 'src/drivers/pc80/rtc/option.c')
| -rw-r--r-- | src/drivers/pc80/rtc/option.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/src/drivers/pc80/rtc/option.c b/src/drivers/pc80/rtc/option.c new file mode 100644 index 0000000000..c7851e5357 --- /dev/null +++ b/src/drivers/pc80/rtc/option.c @@ -0,0 +1,235 @@ +/* + * This file is part of the coreboot project. + * + * 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 + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <console/console.h> +#include <string.h> +#include <cbfs.h> +#include <option.h> +#include <pc80/mc146818rtc.h> +#include <types.h> + +/* option_table.h is autogenerated */ +#include "option_table.h" + +/* Don't warn for checking >= LB_CKS_RANGE_START even though it may be 0. */ +#pragma GCC diagnostic ignored "-Wtype-limits" + +/* + * This routine returns the value of the requested bits. + * input bit = bit count from the beginning of the cmos image + * length = number of bits to include in the value + * ret = a character pointer to where the value is to be returned + * returns CB_SUCCESS = successful, cb_err code if an error occurred + */ +static enum cb_err get_cmos_value(unsigned long bit, unsigned long length, + void *vret) +{ + unsigned char *ret; + unsigned long byte, byte_bit; + unsigned long i; + unsigned char uchar; + + /* + * The table is checked when it is built to ensure all + * values are valid. + */ + ret = vret; + byte = bit / 8; /* find the byte where the data starts */ + byte_bit = bit % 8; /* find the bit in the byte where the data starts */ + if (length < 9) { /* one byte or less */ + uchar = cmos_read(byte); /* load the byte */ + uchar >>= byte_bit; /* shift the bits to byte align */ + /* clear unspecified bits */ + ret[0] = uchar & ((1 << length) - 1); + } else { /* more than one byte so transfer the whole bytes */ + for (i = 0; length; i++, length -= 8, byte++) { + /* load the byte */ + ret[i] = cmos_read(byte); + } + } + return CB_SUCCESS; +} + +static enum cb_err locate_cmos_layout(struct region_device *rdev) +{ + uint32_t cbfs_type = CBFS_COMPONENT_CMOS_LAYOUT; + MAYBE_STATIC_BSS struct cbfsf fh = {}; + + /* + * In case VBOOT is enabled and this function is called from SMM, + * we have multiple CMOS layout files and to locate them we'd need to + * include VBOOT into SMM... + * + * Support only one CMOS layout in the 'COREBOOT' region for now. + */ + if (!region_device_sz(&(fh.data))) { + if (cbfs_locate_file_in_region(&fh, "COREBOOT", "cmos_layout.bin", + &cbfs_type)) { + printk(BIOS_ERR, "RTC: cmos_layout.bin could not be found. " + "Options are disabled\n"); + return CB_CMOS_LAYOUT_NOT_FOUND; + } + } + + cbfs_file_data(rdev, &fh); + + return CB_SUCCESS; +} + +enum cb_err cmos_get_option(void *dest, const char *name) +{ + struct cmos_option_table *ct; + struct region_device rdev; + struct cmos_entries *ce; + size_t namelen; + int found = 0; + + /* Figure out how long name is */ + namelen = strnlen(name, CMOS_MAX_NAME_LENGTH); + + if (locate_cmos_layout(&rdev) != CB_SUCCESS) { + return CB_CMOS_LAYOUT_NOT_FOUND; + } + ct = rdev_mmap_full(&rdev); + if (!ct) { + printk(BIOS_ERR, "RTC: cmos_layout.bin could not be mapped. " + "Options are disabled\n"); + + return CB_CMOS_LAYOUT_NOT_FOUND; + } + + /* find the requested entry record */ + ce = (struct cmos_entries *)((unsigned char *)ct + ct->header_length); + for (; ce->tag == LB_TAG_OPTION; + ce = (struct cmos_entries *)((unsigned char *)ce + ce->size)) { + if (memcmp(ce->name, name, namelen) == 0) { + found = 1; + break; + } + } + if (!found) { + printk(BIOS_DEBUG, "No CMOS option '%s'.\n", name); + rdev_munmap(&rdev, ct); + return CB_CMOS_OPTION_NOT_FOUND; + } + + if (!cmos_checksum_valid(LB_CKS_RANGE_START, LB_CKS_RANGE_END, LB_CKS_LOC)) { + rdev_munmap(&rdev, ct); + return CB_CMOS_CHECKSUM_INVALID; + } + if (get_cmos_value(ce->bit, ce->length, dest) != CB_SUCCESS) { + rdev_munmap(&rdev, ct); + return CB_CMOS_ACCESS_ERROR; + } + rdev_munmap(&rdev, ct); + return CB_SUCCESS; +} + +static enum cb_err set_cmos_value(unsigned long bit, unsigned long length, + void *vret) +{ + unsigned char *ret; + unsigned long byte, byte_bit; + unsigned long i; + unsigned char uchar, mask; + unsigned int chksum_update_needed = 0; + + ret = vret; + byte = bit / 8; /* find the byte where the data starts */ + byte_bit = bit % 8; /* find the bit where the data starts */ + if (length <= 8) { /* one byte or less */ + mask = (1 << length) - 1; + mask <<= byte_bit; + + uchar = cmos_read(byte); + uchar &= ~mask; + uchar |= (ret[0] << byte_bit); + cmos_write(uchar, byte); + if (byte >= LB_CKS_RANGE_START && byte <= LB_CKS_RANGE_END) + chksum_update_needed = 1; + } else { /* more that one byte so transfer the whole bytes */ + if (byte_bit || length % 8) + return CB_ERR_ARG; + + for (i = 0; length; i++, length -= 8, byte++) { + cmos_write(ret[i], byte); + if (byte >= LB_CKS_RANGE_START && + byte <= LB_CKS_RANGE_END) + chksum_update_needed = 1; + } + } + + if (chksum_update_needed) { + cmos_set_checksum(LB_CKS_RANGE_START, LB_CKS_RANGE_END, + LB_CKS_LOC); + } + return CB_SUCCESS; +} + +enum cb_err cmos_set_option(const char *name, void *value) +{ + struct cmos_option_table *ct; + struct region_device rdev; + struct cmos_entries *ce; + unsigned long length; + size_t namelen; + int found = 0; + + /* Figure out how long name is */ + namelen = strnlen(name, CMOS_MAX_NAME_LENGTH); + + if (locate_cmos_layout(&rdev) != CB_SUCCESS) { + return CB_CMOS_LAYOUT_NOT_FOUND; + } + ct = rdev_mmap_full(&rdev); + if (!ct) { + printk(BIOS_ERR, "RTC: cmos_layout.bin could not be mapped. " + "Options are disabled\n"); + + return CB_CMOS_LAYOUT_NOT_FOUND; + } + + /* find the requested entry record */ + ce = (struct cmos_entries *)((unsigned char *)ct + ct->header_length); + for (; ce->tag == LB_TAG_OPTION; + ce = (struct cmos_entries *)((unsigned char *)ce + ce->size)) { + if (memcmp(ce->name, name, namelen) == 0) { + found = 1; + break; + } + } + if (!found) { + printk(BIOS_DEBUG, "WARNING: No CMOS option '%s'.\n", name); + rdev_munmap(&rdev, ct); + return CB_CMOS_OPTION_NOT_FOUND; + } + + length = ce->length; + if (ce->config == 's') { + length = MAX(strlen((const char *)value) * 8, ce->length - 8); + /* make sure the string is null terminated */ + if (set_cmos_value(ce->bit + ce->length - 8, 8, &(u8[]){0}) + != CB_SUCCESS) { + rdev_munmap(&rdev, ct); + return CB_CMOS_ACCESS_ERROR; + } + } + + if (set_cmos_value(ce->bit, length, value) != CB_SUCCESS) { + rdev_munmap(&rdev, ct); + return CB_CMOS_ACCESS_ERROR; + } + + rdev_munmap(&rdev, ct); + return CB_SUCCESS; +} |