From 9b7311d4f94630fdef2dd26180c1e344f11c7272 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Rafa=C5=82=20Mi=C5=82ecki?= Date: Thu, 2 Nov 2023 09:08:54 +0100 Subject: [PATCH] bcm53xx: add the latest fix version of brcm_nvram MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit It was just sent for upstream. Signed-off-by: Rafał Miłecki (cherry picked from commit 943bd3c9f6244c928cd168302d638a6a218fd4e6) --- ..._nvram-store-a-copy-of-NVRAM-content.patch | 246 ++++++++++++++++++ 1 file changed, 246 insertions(+) create mode 100644 target/linux/bcm53xx/patches-5.10/181-nvmem-brcm_nvram-store-a-copy-of-NVRAM-content.patch diff --git a/target/linux/bcm53xx/patches-5.10/181-nvmem-brcm_nvram-store-a-copy-of-NVRAM-content.patch b/target/linux/bcm53xx/patches-5.10/181-nvmem-brcm_nvram-store-a-copy-of-NVRAM-content.patch new file mode 100644 index 0000000000..f79aa84a92 --- /dev/null +++ b/target/linux/bcm53xx/patches-5.10/181-nvmem-brcm_nvram-store-a-copy-of-NVRAM-content.patch @@ -0,0 +1,246 @@ +From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= +Date: Thu, 14 Sep 2023 07:59:09 +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 + +This driver uses MMIO access for reading NVRAM from a flash device. +Underneath there is a flash controller that reads data and provides +mapping window. + +Using MMIO interface affects controller configuration and may break real +controller driver. It was reported by multiple users of devices with +NVRAM stored on NAND. + +Modify driver to read & cache NVRAM content during init and use that +copy to provide NVMEM data when requested. On NAND flashes due to their +alignment NVRAM partitions can be quite big (1 MiB and more) while +actual NVRAM content stays quite small (usually 16 to 32 KiB). To avoid +allocating so much memory check for actual data length. + +Link: https://lore.kernel.org/linux-mtd/CACna6rwf3_9QVjYcM+847biTX=K0EoWXuXcSMkJO1Vy_5vmVqA@mail.gmail.com/ +Fixes: 3fef9ed0627a ("nvmem: brcm_nvram: new driver exposing Broadcom's NVRAM") +Cc: Arınç ÜNAL +Cc: Florian Fainelli +Cc: Scott Branden +Signed-off-by: Rafał Miłecki +Acked-by: Arınç ÜNAL +--- + drivers/nvmem/brcm_nvram.c | 134 ++++++++++++++++++++++++++----------- + 1 file changed, 94 insertions(+), 40 deletions(-) + +--- a/drivers/nvmem/brcm_nvram.c ++++ b/drivers/nvmem/brcm_nvram.c +@@ -15,9 +15,23 @@ + + #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; +- void __iomem *base; ++ size_t nvmem_size; ++ uint8_t *data; ++ size_t data_len; ++ uint8_t padding_byte; + struct nvmem_cell_info *cells; + int ncells; + }; +@@ -34,10 +48,47 @@ static int brcm_nvram_read(void *context + size_t bytes) + { + struct brcm_nvram *priv = context; +- u8 *dst = val; ++ 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; + +- while (bytes--) +- *dst++ = readb(priv->base + offset++); ++ 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; + } +@@ -46,8 +97,13 @@ static int brcm_nvram_add_cells(struct b + size_t len) + { + struct device *dev = priv->dev; +- char *var, *value, *eq; ++ 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); +@@ -57,60 +113,61 @@ static int brcm_nvram_add_cells(struct b + } + + priv->cells = devm_kcalloc(dev, priv->ncells, sizeof(*priv->cells), GFP_KERNEL); +- if (!priv->cells) +- return -ENOMEM; ++ 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 = devm_kstrdup(dev, var, GFP_KERNEL); +- if (!priv->cells[idx].name) +- return -ENOMEM; ++ 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); + } + +- return 0; ++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; +- struct brcm_nvram_header header; +- uint8_t *data; + 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); +- +- data = kzalloc(len, GFP_KERNEL); +- if (!data) +- return -ENOMEM; +- +- memcpy_fromio(data, priv->base, len); +- data[len - 1] = '\0'; +- +- err = brcm_nvram_add_cells(priv, data, len); +- if (err) { +- dev_err(dev, "Failed to add cells: %d\n", err); +- return err; ++ 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; + } + +- kfree(data); ++ err = brcm_nvram_add_cells(priv, priv->data, len); ++ if (err) ++ dev_err(dev, "Failed to add cells: %d\n", err); + + return 0; + } +@@ -122,7 +179,6 @@ static int brcm_nvram_probe(struct platf + .reg_read = brcm_nvram_read, + }; + struct device *dev = &pdev->dev; +- struct resource *res; + struct brcm_nvram *priv; + int err; + +@@ -131,21 +187,19 @@ 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); ++ err = brcm_nvram_copy_data(priv, pdev); ++ if (err) ++ return err; + + err = brcm_nvram_parse(priv); + if (err) + return err; + +- bcm47xx_nvram_init_from_iomem(priv->base, resource_size(res)); +- + config.dev = dev; + config.cells = priv->cells; + config.ncells = priv->ncells; + config.priv = priv; +- config.size = resource_size(res); ++ config.size = priv->nvmem_size; + + return PTR_ERR_OR_ZERO(devm_nvmem_register(dev, &config)); + } -- 2.30.2