openwrt/target/linux/bcm53xx/patches-5.15/800-nvmem-brcm_nvram-store-a-copy-of-NVRAM-content.patch
Rafał Miłecki bcd76dc7d8 bcm53xx: store a copy of NVRAM content in NVMEM driver
This stops NVMEM driver from using MMIO access past booting and messing
with NAND controller state.

Link: https://forum.openwrt.org/t/asus-rt-ac88u-hw-a6-broken-in-22-03-3/147882
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2023-09-01 11:37:16 +02:00

129 lines
3.2 KiB
Diff

From a18378409fee1cac0f0c58a4770ff557b498c778 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
Date: Fri, 1 Sep 2023 10:44:26 +0200
Subject: [PATCH] nvmem: brcm_nvram: store a copy of NVRAM content
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
drivers/nvmem/brcm_nvram.c | 54 +++++++++++++++++++-------------------
1 file changed, 27 insertions(+), 27 deletions(-)
--- a/drivers/nvmem/brcm_nvram.c
+++ b/drivers/nvmem/brcm_nvram.c
@@ -19,7 +19,7 @@
struct brcm_nvram {
struct device *dev;
- void __iomem *base;
+ uint8_t *data;
struct nvmem_cell_info *cells;
int ncells;
};
@@ -36,10 +36,8 @@ static int brcm_nvram_read(void *context
size_t bytes)
{
struct brcm_nvram *priv = context;
- u8 *dst = val;
- while (bytes--)
- *dst++ = readb(priv->base + offset++);
+ memcpy(val, priv->data + offset, bytes);
return 0;
}
@@ -110,35 +108,27 @@ static int brcm_nvram_add_cells(struct b
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;
- struct brcm_nvram_header header;
- uint8_t *data;
+ uint8_t tmp;
size_t len;
int err;
- memcpy_fromio(&header, priv->base, sizeof(header));
-
- if (memcmp(header.magic, NVRAM_MAGIC, 4)) {
+ if (memcmp(header->magic, NVRAM_MAGIC, 4)) {
dev_err(dev, "Invalid NVRAM magic\n");
return -EINVAL;
}
- len = le32_to_cpu(header.len);
+ len = le32_to_cpu(header->len);
- data = kzalloc(len, GFP_KERNEL);
- if (!data)
- return -ENOMEM;
-
- memcpy_fromio(data, priv->base, len);
- data[len - 1] = '\0';
+ tmp = priv->data[len - 1];
+ priv->data[len - 1] = '\0';
- err = brcm_nvram_add_cells(priv, data, len);
- if (err) {
+ err = brcm_nvram_add_cells(priv, priv->data, len);
+ if (err)
dev_err(dev, "Failed to add cells: %d\n", err);
- return err;
- }
- kfree(data);
+ priv->data[len - 1] = tmp;
return 0;
}
@@ -150,8 +140,10 @@ static int brcm_nvram_probe(struct platf
.reg_read = brcm_nvram_read,
};
struct device *dev = &pdev->dev;
- struct resource *res;
struct brcm_nvram *priv;
+ struct resource *res;
+ void __iomem *base;
+ size_t size;
int err;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
@@ -159,21 +151,29 @@ static int brcm_nvram_probe(struct platf
return -ENOMEM;
priv->dev = dev;
- priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
- if (IS_ERR(priv->base))
- return PTR_ERR(priv->base);
+ base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ size = resource_size(res);
+
+ priv->data = kzalloc(size, GFP_KERNEL);
+ if (!priv->data)
+ return -ENOMEM;
+
+ memcpy_fromio(priv->data, base, size);
err = brcm_nvram_parse(priv);
if (err)
return err;
- bcm47xx_nvram_init_from_iomem(priv->base, resource_size(res));
+ bcm47xx_nvram_init_from_iomem(base, size);
config.dev = dev;
config.cells = priv->cells;
config.ncells = priv->ncells;
config.priv = priv;
- config.size = resource_size(res);
+ config.size = size;
return PTR_ERR_OR_ZERO(devm_nvmem_register(dev, &config));
}