summaryrefslogtreecommitdiff
path: root/src/drivers/pc80/rtc/option.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/drivers/pc80/rtc/option.c')
-rw-r--r--src/drivers/pc80/rtc/option.c235
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;
+}