summaryrefslogtreecommitdiffstats
path: root/drivers/nvmem/brcm_nvram.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/nvmem/brcm_nvram.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/nvmem/brcm_nvram.c')
-rw-r--r--drivers/nvmem/brcm_nvram.c257
1 files changed, 257 insertions, 0 deletions
diff --git a/drivers/nvmem/brcm_nvram.c b/drivers/nvmem/brcm_nvram.c
new file mode 100644
index 0000000000..5cdf339cfb
--- /dev/null
+++ b/drivers/nvmem/brcm_nvram.c
@@ -0,0 +1,257 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2021 Rafał Miłecki <rafal@milecki.pl>
+ */
+
+#include <linux/bcm47xx_nvram.h>
+#include <linux/etherdevice.h>
+#include <linux/if_ether.h>
+#include <linux/io.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define NVRAM_MAGIC "FLSH"
+
+/**
+ * struct brcm_nvram - driver state internal struct
+ *
+ * @dev: NVMEM device pointer
+ * @nvmem_size: Size of the whole space available for NVRAM
+ * @data: NVRAM data copy stored to avoid poking underlaying flash controller
+ * @data_len: NVRAM data size
+ * @padding_byte: Padding value used to fill remaining space
+ * @cells: Array of discovered NVMEM cells
+ * @ncells: Number of elements in cells
+ */
+struct brcm_nvram {
+ struct device *dev;
+ size_t nvmem_size;
+ uint8_t *data;
+ size_t data_len;
+ uint8_t padding_byte;
+ struct nvmem_cell_info *cells;
+ int ncells;
+};
+
+struct brcm_nvram_header {
+ char magic[4];
+ __le32 len;
+ __le32 crc_ver_init; /* 0:7 crc, 8:15 ver, 16:31 sdram_init */
+ __le32 config_refresh; /* 0:15 sdram_config, 16:31 sdram_refresh */
+ __le32 config_ncdl; /* ncdl values for memc */
+};
+
+static int brcm_nvram_read(void *context, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct brcm_nvram *priv = context;
+ size_t to_copy;
+
+ if (offset + bytes > priv->data_len)
+ to_copy = max_t(ssize_t, (ssize_t)priv->data_len - offset, 0);
+ else
+ to_copy = bytes;
+
+ memcpy(val, priv->data + offset, to_copy);
+
+ memset((uint8_t *)val + to_copy, priv->padding_byte, bytes - to_copy);
+
+ return 0;
+}
+
+static int brcm_nvram_copy_data(struct brcm_nvram *priv, struct platform_device *pdev)
+{
+ struct resource *res;
+ void __iomem *base;
+
+ base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ priv->nvmem_size = resource_size(res);
+
+ priv->padding_byte = readb(base + priv->nvmem_size - 1);
+ for (priv->data_len = priv->nvmem_size;
+ priv->data_len;
+ priv->data_len--) {
+ if (readb(base + priv->data_len - 1) != priv->padding_byte)
+ break;
+ }
+ WARN(priv->data_len > SZ_128K, "Unexpected (big) NVRAM size: %zu B\n", priv->data_len);
+
+ priv->data = devm_kzalloc(priv->dev, priv->data_len, GFP_KERNEL);
+ if (!priv->data)
+ return -ENOMEM;
+
+ memcpy_fromio(priv->data, base, priv->data_len);
+
+ bcm47xx_nvram_init_from_iomem(base, priv->data_len);
+
+ return 0;
+}
+
+static int brcm_nvram_read_post_process_macaddr(void *context, const char *id, int index,
+ unsigned int offset, void *buf, size_t bytes)
+{
+ u8 mac[ETH_ALEN];
+
+ if (bytes != 3 * ETH_ALEN - 1)
+ return -EINVAL;
+
+ if (!mac_pton(buf, mac))
+ return -EINVAL;
+
+ if (index)
+ eth_addr_add(mac, index);
+
+ ether_addr_copy(buf, mac);
+
+ return 0;
+}
+
+static int brcm_nvram_add_cells(struct brcm_nvram *priv, uint8_t *data,
+ size_t len)
+{
+ struct device *dev = priv->dev;
+ char *var, *value;
+ uint8_t tmp;
+ int idx;
+ int err = 0;
+
+ tmp = priv->data[len - 1];
+ priv->data[len - 1] = '\0';
+
+ priv->ncells = 0;
+ for (var = data + sizeof(struct brcm_nvram_header);
+ var < (char *)data + len && *var;
+ var += strlen(var) + 1) {
+ priv->ncells++;
+ }
+
+ priv->cells = devm_kcalloc(dev, priv->ncells, sizeof(*priv->cells), GFP_KERNEL);
+ if (!priv->cells) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ for (var = data + sizeof(struct brcm_nvram_header), idx = 0;
+ var < (char *)data + len && *var;
+ var = value + strlen(value) + 1, idx++) {
+ char *eq, *name;
+
+ eq = strchr(var, '=');
+ if (!eq)
+ break;
+ *eq = '\0';
+ name = devm_kstrdup(dev, var, GFP_KERNEL);
+ *eq = '=';
+ if (!name) {
+ err = -ENOMEM;
+ goto out;
+ }
+ value = eq + 1;
+
+ priv->cells[idx].name = name;
+ priv->cells[idx].offset = value - (char *)data;
+ priv->cells[idx].bytes = strlen(value);
+ priv->cells[idx].np = of_get_child_by_name(dev->of_node, priv->cells[idx].name);
+ if (!strcmp(name, "et0macaddr") ||
+ !strcmp(name, "et1macaddr") ||
+ !strcmp(name, "et2macaddr")) {
+ priv->cells[idx].raw_len = strlen(value);
+ priv->cells[idx].bytes = ETH_ALEN;
+ priv->cells[idx].read_post_process = brcm_nvram_read_post_process_macaddr;
+ }
+ }
+
+out:
+ priv->data[len - 1] = tmp;
+ return err;
+}
+
+static int brcm_nvram_parse(struct brcm_nvram *priv)
+{
+ struct brcm_nvram_header *header = (struct brcm_nvram_header *)priv->data;
+ struct device *dev = priv->dev;
+ size_t len;
+ int err;
+
+ if (memcmp(header->magic, NVRAM_MAGIC, 4)) {
+ dev_err(dev, "Invalid NVRAM magic\n");
+ return -EINVAL;
+ }
+
+ len = le32_to_cpu(header->len);
+ if (len > priv->nvmem_size) {
+ dev_err(dev, "NVRAM length (%zd) exceeds mapped size (%zd)\n", len,
+ priv->nvmem_size);
+ return -EINVAL;
+ }
+
+ err = brcm_nvram_add_cells(priv, priv->data, len);
+ if (err)
+ dev_err(dev, "Failed to add cells: %d\n", err);
+
+ return 0;
+}
+
+static int brcm_nvram_probe(struct platform_device *pdev)
+{
+ struct nvmem_config config = {
+ .name = "brcm-nvram",
+ .reg_read = brcm_nvram_read,
+ };
+ struct device *dev = &pdev->dev;
+ struct brcm_nvram *priv;
+ int err;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+ priv->dev = dev;
+
+ err = brcm_nvram_copy_data(priv, pdev);
+ if (err)
+ return err;
+
+ err = brcm_nvram_parse(priv);
+ if (err)
+ return err;
+
+ config.dev = dev;
+ config.cells = priv->cells;
+ config.ncells = priv->ncells;
+ config.priv = priv;
+ config.size = priv->nvmem_size;
+
+ return PTR_ERR_OR_ZERO(devm_nvmem_register(dev, &config));
+}
+
+static const struct of_device_id brcm_nvram_of_match_table[] = {
+ { .compatible = "brcm,nvram", },
+ {},
+};
+
+static struct platform_driver brcm_nvram_driver = {
+ .probe = brcm_nvram_probe,
+ .driver = {
+ .name = "brcm_nvram",
+ .of_match_table = brcm_nvram_of_match_table,
+ },
+};
+
+static int __init brcm_nvram_init(void)
+{
+ return platform_driver_register(&brcm_nvram_driver);
+}
+
+subsys_initcall_sync(brcm_nvram_init);
+
+MODULE_AUTHOR("Rafał Miłecki");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(of, brcm_nvram_of_match_table);