[PATCH 0/2] nvmem: fixes for 6.7

[PATCH 0/2] nvmem: fixes for 6.7

[srinivas.kandagatla]

From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

Hi Greg, 

Here are two fixes in nvmem for 6.7, if its not too late could you queue
these for next possible rc.

Thanks,
Srini

MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

*** BLURB HERE ***

Fabio Estevam (1):
  dt-bindings: nvmem: mxs-ocotp: Document fsl,ocotp

Rafał Miłecki (1):
  nvmem: brcm_nvram: store a copy of NVRAM content

 .../devicetree/bindings/nvmem/mxs-ocotp.yaml  |  10 +-
 drivers/nvmem/brcm_nvram.c                    | 134 ++++++++++++------
 2 files changed, 100 insertions(+), 44 deletions(-)

-- 
2.25.1

[PATCH 1/2] dt-bindings: nvmem: mxs-ocotp: Document fsl,ocotp

[srinivas.kandagatla]

From: Fabio Estevam <festevam@denx.de>

Both imx23.dtsi and imx28.dtsi describe the OCOTP nodes in
the format:

compatible = "fsl,imx28-ocotp", "fsl,ocotp";

Document the "fsl,ocotp" entry to fix the following schema
warning:

efuse@8002c000: compatible: ['fsl,imx23-ocotp', 'fsl,ocotp'] is too long
from schema $id: http://devicetree.org/schemas/nvmem/mxs-ocotp.yaml#

Fixes: 2c504460f502 ("dt-bindings: nvmem: Convert MXS OCOTP to json-schema")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 Documentation/devicetree/bindings/nvmem/mxs-ocotp.yaml | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/nvmem/mxs-ocotp.yaml b/Documentation/devicetree/bindings/nvmem/mxs-ocotp.yaml
index f43186f98607..d9287be89877 100644
--- a/Documentation/devicetree/bindings/nvmem/mxs-ocotp.yaml
+++ b/Documentation/devicetree/bindings/nvmem/mxs-ocotp.yaml
@@ -15,9 +15,11 @@ allOf:
 
 properties:
   compatible:
-    enum:
-      - fsl,imx23-ocotp
-      - fsl,imx28-ocotp
+    items:
+      - enum:
+          - fsl,imx23-ocotp
+          - fsl,imx28-ocotp
+      - const: fsl,ocotp
 
   reg:
     maxItems: 1
@@ -35,7 +37,7 @@ unevaluatedProperties: false
 examples:
   - |
     ocotp: efuse@8002c000 {
-        compatible = "fsl,imx28-ocotp";
+        compatible = "fsl,imx28-ocotp", "fsl,ocotp";
         #address-cells = <1>;
         #size-cells = <1>;
         reg = <0x8002c000 0x2000>;
-- 
2.25.1

[PATCH 2/2] nvmem: brcm_nvram: store a copy of NVRAM content

[srinivas.kandagatla]

From: Rafał Miłecki <rafal@milecki.pl>

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: <Stable@vger.kernel.org>
Cc: Arınç ÜNAL <arinc.unal@arinc9.com>
Cc: Florian Fainelli <florian.fainelli@broadcom.com>
Cc: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/nvmem/brcm_nvram.c | 134 ++++++++++++++++++++++++++-----------
 1 file changed, 94 insertions(+), 40 deletions(-)

diff --git a/drivers/nvmem/brcm_nvram.c b/drivers/nvmem/brcm_nvram.c
index 9737104f3b76..5cdf339cfbec 100644
--- a/drivers/nvmem/brcm_nvram.c
+++ b/drivers/nvmem/brcm_nvram.c
@@ -17,9 +17,23 @@
 
 #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;
 };
@@ -36,10 +50,47 @@ static int brcm_nvram_read(void *context, unsigned int offset, void *val,
 			   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;
+
+	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);
 
-	while (bytes--)
-		*dst++ = readb(priv->base + offset++);
+	bcm47xx_nvram_init_from_iomem(base, priv->data_len);
 
 	return 0;
 }
@@ -67,8 +118,13 @@ static int brcm_nvram_add_cells(struct brcm_nvram *priv, uint8_t *data,
 				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);
@@ -78,67 +134,68 @@ static int brcm_nvram_add_cells(struct brcm_nvram *priv, uint8_t *data,
 	}
 
 	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);
-		if (!strcmp(var, "et0macaddr") ||
-		    !strcmp(var, "et1macaddr") ||
-		    !strcmp(var, "et2macaddr")) {
+		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;
 		}
 	}
 
-	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;
 }
@@ -150,7 +207,6 @@ static int brcm_nvram_probe(struct platform_device *pdev)
 		.reg_read = brcm_nvram_read,
 	};
 	struct device *dev = &pdev->dev;
-	struct resource *res;
 	struct brcm_nvram *priv;
 	int err;
 
@@ -159,21 +215,19 @@ static int brcm_nvram_probe(struct platform_device *pdev)
 		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));
 }
-- 
2.25.1

Re: [PATCH 0/2] nvmem: fixes for 6.7

[Greg KH]

On Fri, Dec 15, 2023 at 11:13:56AM +0000, srinivas.kandagatla@linaro.org wrote:
> From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> 
> Hi Greg, 
> 
> Here are two fixes in nvmem for 6.7, if its not too late could you queue
> these for next possible rc.
> 
> Thanks,
> Srini
> 
> MIME-Version: 1.0
> Content-Type: text/plain; charset=UTF-8
> Content-Transfer-Encoding: 8bit
> 
> *** BLURB HERE ***

No blurb?

Re: [PATCH 0/2] nvmem: fixes for 6.7

[Srinivas Kandagatla]

On 15/12/2023 11:26, Greg KH wrote:
> On Fri, Dec 15, 2023 at 11:13:56AM +0000, srinivas.kandagatla@linaro.org wrote:
>> From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
>>
>> Hi Greg,
>>
>> Here are two fixes in nvmem for 6.7, if its not too late could you queue
>> these for next possible rc.
>>
>> Thanks,
>> Srini
>>
>> MIME-Version: 1.0
>> Content-Type: text/plain; charset=UTF-8
>> Content-Transfer-Encoding: 8bit
>>
>> *** BLURB HERE ***
> 

Forgot to delete this.

> No blurb?

   ____  _     _    _ _____  ____
  |  _ \| |   | |  | |  __ \|  _ \
  | |_) | |   | |  | | |__) | |_) |
  |  _ <| |   | |  | |  _  /|  _ <
  | |_) | |___| |__| | | \ \| |_) |
  |____/|______\____/|_|  \_\____/

:-)


--srini

Re: [PATCH 0/2] nvmem: fixes for 6.7

[Greg KH]

On Fri, Dec 15, 2023 at 11:31:03AM +0000, Srinivas Kandagatla wrote:
> 
> 
> On 15/12/2023 11:26, Greg KH wrote:
> > On Fri, Dec 15, 2023 at 11:13:56AM +0000, srinivas.kandagatla@linaro.org wrote:
> > > From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> > > 
> > > Hi Greg,
> > > 
> > > Here are two fixes in nvmem for 6.7, if its not too late could you queue
> > > these for next possible rc.
> > > 
> > > Thanks,
> > > Srini
> > > 
> > > MIME-Version: 1.0
> > > Content-Type: text/plain; charset=UTF-8
> > > Content-Transfer-Encoding: 8bit
> > > 
> > > *** BLURB HERE ***
> > 
> 
> Forgot to delete this.
> 
> > No blurb?
> 
>   ____  _     _    _ _____  ____
>  |  _ \| |   | |  | |  __ \|  _ \
>  | |_) | |   | |  | | |__) | |_) |
>  |  _ <| |   | |  | |  _  /|  _ <
>  | |_) | |___| |__| | | \ \| |_) |
>  |____/|______\____/|_|  \_\____/
> 
> :-)

Much better, thanks!  I'll go queue these up now :)