[PATCH 0/3] Update for the Broadcom STB DPFE driver

[PATCH 0/3] Update for the Broadcom STB DPFE driver

[Markus Mayer]

This series primarily introduces a new way of passing information from
the DCPU to the host CPU.

Previously, all communication was via the DCPU data RAM. This
communication mode is still supported. In addition, we now support
passing data via the message RAM. The driver will dynamically detect
which method to use upon receiving a reply.

The series also contains two fixes to the driver that have no direct
relation with the new communication feature.

Markus Mayer (3):
  memory: brcmstb: dpfe: properly mask vendor error bits
  memory: brcmstb: dpfe: fix type declaration of variable "ret"
  memory: brcmstb: dpfe: support new way of passing data from the DCPU

 drivers/memory/brcmstb_dpfe.c | 74 +++++++++++++++++++++++++++++++++++--------
 1 file changed, 60 insertions(+), 14 deletions(-)

-- 
2.7.4

[PATCH 1/3] memory: brcmstb: dpfe: properly mask vendor error bits

[Markus Mayer]

We were printing the entire 32 bit register rather than just the lower
8 bits. Anything above bit 7 is reserved and may be any random value.

Fixes: 2f330caff577 ("memory: brcmstb: Add driver for DPFE")
Signed-off-by: Markus Mayer <mmayer@broadcom.com>
---
 drivers/memory/brcmstb_dpfe.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
index 0a7bdbed3a6f..088153760e52 100644
--- a/drivers/memory/brcmstb_dpfe.c
+++ b/drivers/memory/brcmstb_dpfe.c
@@ -603,7 +603,8 @@ static ssize_t show_vendor(struct device *dev, struct device_attribute *devattr,
 		       readl_relaxed(info + DRAM_VENDOR_MR6) & DRAM_VENDOR_MASK,
 		       readl_relaxed(info + DRAM_VENDOR_MR7) & DRAM_VENDOR_MASK,
 		       readl_relaxed(info + DRAM_VENDOR_MR8) & DRAM_VENDOR_MASK,
-		       readl_relaxed(info + DRAM_VENDOR_ERROR));
+		       readl_relaxed(info + DRAM_VENDOR_ERROR) &
+				     DRAM_VENDOR_MASK);
 }
 
 static int brcmstb_dpfe_resume(struct platform_device *pdev)
-- 
2.7.4

[PATCH 2/3] memory: brcmstb: dpfe: fix type declaration of variable "ret"

[Markus Mayer]

In some functions, variable "ret" should be ssize_t, so we fix it.

Fixes: 2f330caff577 ("memory: brcmstb: Add driver for DPFE")
Signed-off-by: Markus Mayer <mmayer@broadcom.com>
---
 drivers/memory/brcmstb_dpfe.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
index 088153760e52..2013a91217a9 100644
--- a/drivers/memory/brcmstb_dpfe.c
+++ b/drivers/memory/brcmstb_dpfe.c
@@ -507,7 +507,7 @@ static ssize_t show_info(struct device *dev, struct device_attribute *devattr,
 {
 	u32 response[MSG_FIELD_MAX];
 	unsigned int info;
-	int ret;
+	ssize_t ret;
 
 	ret = generic_show(DPFE_CMD_GET_INFO, response, dev, buf);
 	if (ret)
@@ -531,7 +531,7 @@ static ssize_t show_refresh(struct device *dev,
 	unsigned int offset;
 	u8 refresh, sr_abort, ppre, thermal_offs, tuf;
 	u32 mr4;
-	int ret;
+	ssize_t ret;
 
 	ret = generic_show(DPFE_CMD_GET_REFRESH, response, dev, buf);
 	if (ret)
@@ -588,7 +588,7 @@ static ssize_t show_vendor(struct device *dev, struct device_attribute *devattr,
 	struct private_data *priv;
 	void __iomem *info;
 	unsigned int offset;
-	int ret;
+	ssize_t ret;
 
 	ret = generic_show(DPFE_CMD_GET_VENDOR, response, dev, buf);
 	if (ret)
-- 
2.7.4

[PATCH 3/3] memory: brcmstb: dpfe: support new way of passing data from the DCPU

[Markus Mayer]

The DCPU can now send message data in two ways:
  - via the data RAM, as before (this is now message type 0)
  - via the message RAM (this is message type 1)

In order to support both methods, we check the message type of the
response (bits 31:28) and then treat the offset (bits 27:0)
accordingly.

Signed-off-by: Markus Mayer <mmayer@broadcom.com>
---
 drivers/memory/brcmstb_dpfe.c | 65 ++++++++++++++++++++++++++++++++++++-------
 1 file changed, 55 insertions(+), 10 deletions(-)

diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
index 2013a91217a9..e9c1485c32b9 100644
--- a/drivers/memory/brcmstb_dpfe.c
+++ b/drivers/memory/brcmstb_dpfe.c
@@ -45,8 +45,16 @@
 #define REG_TO_DCPU_MBOX	0x10
 #define REG_TO_HOST_MBOX	0x14
 
+/* Macros to process offsets returned by the DCPU */
+#define DRAM_MSG_ADDR_OFFSET	0x0
+#define DRAM_MSG_TYPE_OFFSET	0x1c
+#define DRAM_MSG_ADDR_MASK	((1UL << DRAM_MSG_TYPE_OFFSET) - 1)
+#define DRAM_MSG_TYPE_MASK	((1UL << \
+				 (BITS_PER_LONG - DRAM_MSG_TYPE_OFFSET)) - 1)
+
 /* Message RAM */
-#define DCPU_MSG_RAM(x)		(0x100 + (x) * sizeof(u32))
+#define DCPU_MSG_RAM_START	0x100
+#define DCPU_MSG_RAM(x)		(DCPU_MSG_RAM_START + (x) * sizeof(u32))
 
 /* DRAM Info Offsets & Masks */
 #define DRAM_INFO_INTERVAL	0x0
@@ -255,6 +263,40 @@ static unsigned int get_msg_chksum(const u32 msg[])
 	return sum;
 }
 
+static void __iomem *get_msg_ptr(struct private_data *priv, u32 response,
+				 char *buf, ssize_t *size)
+{
+	unsigned int msg_type;
+	unsigned int offset;
+	void __iomem *ptr = NULL;
+
+	msg_type = (response >> DRAM_MSG_TYPE_OFFSET) & DRAM_MSG_TYPE_MASK;
+	offset = (response >> DRAM_MSG_ADDR_OFFSET) & DRAM_MSG_ADDR_MASK;
+
+	/*
+	 * msg_type == 1: the offset is relative to the message RAM
+	 * msg_type == 0: the offset is relative to the data RAM (this is the
+	 *                previous way of passing data)
+	 * msg_type is anything else: there's critical hardware problem
+	 */
+	switch (msg_type) {
+	case 1:
+		ptr = priv->regs + DCPU_MSG_RAM_START + offset;
+		break;
+	case 0:
+		ptr = priv->dmem + offset;
+		break;
+	default:
+		dev_emerg(priv->dev, "invalid message reply from DCPU: %#x\n",
+			response);
+		if (buf && size)
+			*size = sprintf(buf,
+				"FATAL: communication error with DCPU\n");
+	}
+
+	return ptr;
+}
+
 static int __send_command(struct private_data *priv, unsigned int cmd,
 			  u32 result[])
 {
@@ -528,7 +570,6 @@ static ssize_t show_refresh(struct device *dev,
 	u32 response[MSG_FIELD_MAX];
 	void __iomem *info;
 	struct private_data *priv;
-	unsigned int offset;
 	u8 refresh, sr_abort, ppre, thermal_offs, tuf;
 	u32 mr4;
 	ssize_t ret;
@@ -538,8 +579,10 @@ static ssize_t show_refresh(struct device *dev,
 		return ret;
 
 	priv = dev_get_drvdata(dev);
-	offset = response[MSG_ARG0];
-	info = priv->dmem + offset;
+
+	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
+	if (!info)
+		return ret;
 
 	mr4 = readl_relaxed(info + DRAM_INFO_MR4) & DRAM_INFO_MR4_MASK;
 
@@ -561,7 +604,6 @@ static ssize_t store_refresh(struct device *dev, struct device_attribute *attr,
 	u32 response[MSG_FIELD_MAX];
 	struct private_data *priv;
 	void __iomem *info;
-	unsigned int offset;
 	unsigned long val;
 	int ret;
 
@@ -574,8 +616,10 @@ static ssize_t store_refresh(struct device *dev, struct device_attribute *attr,
 	if (ret)
 		return ret;
 
-	offset = response[MSG_ARG0];
-	info = priv->dmem + offset;
+	info = get_msg_ptr(priv, response[MSG_ARG0], NULL, NULL);
+	if (!info)
+		return -EIO;
+
 	writel_relaxed(val, info + DRAM_INFO_INTERVAL);
 
 	return count;
@@ -587,16 +631,17 @@ static ssize_t show_vendor(struct device *dev, struct device_attribute *devattr,
 	u32 response[MSG_FIELD_MAX];
 	struct private_data *priv;
 	void __iomem *info;
-	unsigned int offset;
 	ssize_t ret;
 
 	ret = generic_show(DPFE_CMD_GET_VENDOR, response, dev, buf);
 	if (ret)
 		return ret;
 
-	offset = response[MSG_ARG0];
 	priv = dev_get_drvdata(dev);
-	info = priv->dmem + offset;
+
+	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
+	if (!info)
+		return ret;
 
 	return sprintf(buf, "%#x %#x %#x %#x %#x\n",
 		       readl_relaxed(info + DRAM_VENDOR_MR5) & DRAM_VENDOR_MASK,
-- 
2.7.4

Re: [PATCH 1/3] memory: brcmstb: dpfe: properly mask vendor error bits

[Florian Fainelli]

On Tue, 13 Feb 2018 12:40:38 -0800, Markus Mayer <mmayer@broadcom.com> wrote:
> We were printing the entire 32 bit register rather than just the lower
> 8 bits. Anything above bit 7 is reserved and may be any random value.
> 
> Fixes: 2f330caff577 ("memory: brcmstb: Add driver for DPFE")
> Signed-off-by: Markus Mayer <mmayer@broadcom.com>
> ---

Applied to drivers/fixes, thanks!
--
Florian

Re: [PATCH 2/3] memory: brcmstb: dpfe: fix type declaration of variable "ret"

[Florian Fainelli]

On Tue, 13 Feb 2018 12:40:39 -0800, Markus Mayer <mmayer@broadcom.com> wrote:
> In some functions, variable "ret" should be ssize_t, so we fix it.
> 
> Fixes: 2f330caff577 ("memory: brcmstb: Add driver for DPFE")
> Signed-off-by: Markus Mayer <mmayer@broadcom.com>
> ---

Applied to drivers/fixes, thanks!
--
Florian

Re: [PATCH 3/3] memory: brcmstb: dpfe: support new way of passing data from the DCPU

[Florian Fainelli]

On Tue, 13 Feb 2018 12:40:40 -0800, Markus Mayer <mmayer@broadcom.com> wrote:
> The DCPU can now send message data in two ways:
>   - via the data RAM, as before (this is now message type 0)
>   - via the message RAM (this is message type 1)
> 
> In order to support both methods, we check the message type of the
> response (bits 31:28) and then treat the offset (bits 27:0)
> accordingly.
> 
> Signed-off-by: Markus Mayer <mmayer@broadcom.com>
> ---

Applied to drivers/fixes, thanks!
--
Florian