1 files changed, 41 insertions, 12 deletions

diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
index 5de6bb406fb6..df028faa2d00 100644
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -10,20 +10,21 @@
  * and select subsets of aarch64), a Device Tree node (on arm), or using
  * a kernel module (or command line) parameter with the following syntax:
  *
- *      [qemu_fw_cfg.]ioport=<size>@<base>[:<ctrl_off>:<data_off>]
+ *      [qemu_fw_cfg.]ioport=<size>@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]
  * or
- *      [qemu_fw_cfg.]mmio=<size>@<base>[:<ctrl_off>:<data_off>]
+ *      [qemu_fw_cfg.]mmio=<size>@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]
  *
  * where:
  *      <size>     := size of ioport or mmio range
  *      <base>     := physical base address of ioport or mmio range
  *      <ctrl_off> := (optional) offset of control register
  *      <data_off> := (optional) offset of data register
+ *      <dma_off> := (optional) offset of dma register
  *
  * e.g.:
- *      qemu_fw_cfg.ioport=2@0x510:0:1          (the default on x86)
+ *      qemu_fw_cfg.ioport=12@0x510:0:1:4       (the default on x86)
  * or
- *      qemu_fw_cfg.mmio=0xA@0x9020000:8:0      (the default on arm)
+ *      qemu_fw_cfg.mmio=16@0x9020000:8:0:16    (the default on arm)
  */
 
 #include <linux/module.h>
@@ -45,6 +46,7 @@ static resource_size_t fw_cfg_p_size;
 static void __iomem *fw_cfg_dev_base;
 static void __iomem *fw_cfg_reg_ctrl;
 static void __iomem *fw_cfg_reg_data;
+static void __iomem *fw_cfg_reg_dma;
 
 /* atomic access to fw_cfg device (potentially slow i/o, so using mutex) */
 static DEFINE_MUTEX(fw_cfg_dev_lock);
@@ -104,12 +106,14 @@ static void fw_cfg_io_cleanup(void)
 # if (defined(CONFIG_ARM) || defined(CONFIG_ARM64))
 #  define FW_CFG_CTRL_OFF 0x08
 #  define FW_CFG_DATA_OFF 0x00
+#  define FW_CFG_DMA_OFF 0x10
 # elif (defined(CONFIG_PPC_PMAC) || defined(CONFIG_SPARC32)) /* ppc/mac,sun4m */
 #  define FW_CFG_CTRL_OFF 0x00
 #  define FW_CFG_DATA_OFF 0x02
 # elif (defined(CONFIG_X86) || defined(CONFIG_SPARC64)) /* x86, sun4u */
 #  define FW_CFG_CTRL_OFF 0x00
 #  define FW_CFG_DATA_OFF 0x01
+#  define FW_CFG_DMA_OFF 0x04
 # else
 #  error "QEMU FW_CFG not available on this architecture!"
 # endif
@@ -119,7 +123,7 @@ static void fw_cfg_io_cleanup(void)
 static int fw_cfg_do_platform_probe(struct platform_device *pdev)
 {
         char sig[FW_CFG_SIG_SIZE];
-        struct resource *range, *ctrl, *data;
+        struct resource *range, *ctrl, *data, *dma;
 
         /* acquire i/o range details */
         fw_cfg_is_mmio = false;
@@ -156,6 +160,7 @@ static int fw_cfg_do_platform_probe(struct platform_device *pdev)
         /* were custom register offsets provided (e.g. on the command line)? */
         ctrl = platform_get_resource_byname(pdev, IORESOURCE_REG, "ctrl");
         data = platform_get_resource_byname(pdev, IORESOURCE_REG, "data");
+        dma = platform_get_resource_byname(pdev, IORESOURCE_REG, "dma");
         if (ctrl && data) {
                 fw_cfg_reg_ctrl = fw_cfg_dev_base + ctrl->start;
                 fw_cfg_reg_data = fw_cfg_dev_base + data->start;
@@ -165,6 +170,13 @@ static int fw_cfg_do_platform_probe(struct platform_device *pdev)
                 fw_cfg_reg_data = fw_cfg_dev_base + FW_CFG_DATA_OFF;
         }
 
+        if (dma)
+                fw_cfg_reg_dma = fw_cfg_dev_base + dma->start;
+#ifdef FW_CFG_DMA_OFF
+        else
+                fw_cfg_reg_dma = fw_cfg_dev_base + FW_CFG_DMA_OFF;
+#endif
+
         /* verify fw_cfg device signature */
         if (fw_cfg_read_blob(FW_CFG_SIGNATURE, sig,
                                 0, FW_CFG_SIG_SIZE) < 0 ||
@@ -630,6 +642,7 @@ static struct platform_device *fw_cfg_cmdline_dev;
 /* use special scanf/printf modifier for phys_addr_t, resource_size_t */
 #define PH_ADDR_SCAN_FMT "@%" __PHYS_ADDR_PREFIX "i%n" \
                          ":%" __PHYS_ADDR_PREFIX "i" \
+                         ":%" __PHYS_ADDR_PREFIX "i%n" \
                          ":%" __PHYS_ADDR_PREFIX "i%n"
 
 #define PH_ADDR_PR_1_FMT "0x%" __PHYS_ADDR_PREFIX "x@" \
@@ -639,12 +652,15 @@ static struct platform_device *fw_cfg_cmdline_dev;
                          ":%" __PHYS_ADDR_PREFIX "u" \
                          ":%" __PHYS_ADDR_PREFIX "u"
 
+#define PH_ADDR_PR_4_FMT PH_ADDR_PR_3_FMT \
+                         ":%" __PHYS_ADDR_PREFIX "u"
+
 static int fw_cfg_cmdline_set(const char *arg, const struct kernel_param *kp)
 {
-        struct resource res[3] = {};
+        struct resource res[4] = {};
         char *str;
         phys_addr_t base;
-        resource_size_t size, ctrl_off, data_off;
+        resource_size_t size, ctrl_off, data_off, dma_off;
         int processed, consumed = 0;
 
         /* only one fw_cfg device can exist system-wide, so if one
@@ -660,19 +676,20 @@ static int fw_cfg_cmdline_set(const char *arg, const struct kernel_param *kp)
         /* consume "<size>" portion of command line argument */
         size = memparse(arg, &str);
 
-        /* get "@<base>[:<ctrl_off>:<data_off>]" chunks */
+        /* get "@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]" chunks */
         processed = sscanf(str, PH_ADDR_SCAN_FMT,
                            &base, &consumed,
-                           &ctrl_off, &data_off, &consumed);
+                           &ctrl_off, &data_off, &consumed,
+                           &dma_off, &consumed);
 
-        /* sscanf() must process precisely 1 or 3 chunks:
+        /* sscanf() must process precisely 1, 3 or 4 chunks:
          * <base> is mandatory, optionally followed by <ctrl_off>
-         * and <data_off>;
+         * and <data_off>, and <dma_off>;
          * there must be no extra characters after the last chunk,
          * so str[consumed] must be '\0'.
          */
         if (str[consumed] ||
-            (processed != 1 && processed != 3))
+            (processed != 1 && processed != 3 && processed != 4))
                 return -EINVAL;
 
         res[0].start = base;
@@ -689,6 +706,11 @@ static int fw_cfg_cmdline_set(const char *arg, const struct kernel_param *kp)
                 res[2].start = data_off;
                 res[2].flags = IORESOURCE_REG;
         }
+        if (processed > 3) {
+                res[3].name = "dma";
+                res[3].start = dma_off;
+                res[3].flags = IORESOURCE_REG;
+        }
 
         /* "processed" happens to nicely match the number of resources
          * we need to pass in to this platform device.
@@ -721,6 +743,13 @@ static int fw_cfg_cmdline_get(char *buf, const struct kernel_param *kp)
                                 fw_cfg_cmdline_dev->resource[0].start,
                                 fw_cfg_cmdline_dev->resource[1].start,
                                 fw_cfg_cmdline_dev->resource[2].start);
+        case 4:
+                return snprintf(buf, PAGE_SIZE, PH_ADDR_PR_4_FMT,
+                                resource_size(&fw_cfg_cmdline_dev->resource[0]),
+                                fw_cfg_cmdline_dev->resource[0].start,
+                                fw_cfg_cmdline_dev->resource[1].start,
+                                fw_cfg_cmdline_dev->resource[2].start,
+                                fw_cfg_cmdline_dev->resource[3].start);
         }
 
         /* Should never get here */