memory: brcmstb: dpfe: support new way of passing data from the DCPU

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>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
index 2013a91..e9c1485 100644 (file)
--- 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,