mach-snapdragon: set serial number

In the typical case where we chainload from ABL, the serial number is
available in the DT bootargs. Read it out and set the serial#
environment variable so that it can be used by fastboot.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>

diff --git a/arch/arm/mach-snapdragon/board.c b/arch/arm/mach-snapdragon/board.c
index 3b9178925c8344feac9daa5c72c4e73d71c07f49..09de967b260e93d7638b79bd34b0771e509ac206 100644 (file)
--- a/arch/arm/mach-snapdragon/board.c
+++ b/arch/arm/mach-snapdragon/board.c
@@ -244,6 +244,66 @@ int board_init(void)
        return 0;
 }
 
+/**
+ * out_len includes the trailing null space
+ */
+static int get_cmdline_option(const char *cmdline, const char *key, char *out, int out_len)
+{
+       const char *p, *p_end;
+       int len;
+
+       p = strstr(cmdline, key);
+       if (!p)
+               return -ENOENT;
+
+       p += strlen(key);
+       p_end = strstr(p, " ");
+       if (!p_end)
+               return -ENOENT;
+
+       len = p_end - p;
+       if (len > out_len)
+               len = out_len;
+
+       strncpy(out, p, len);
+       out[len] = '\0';
+
+       return 0;
+}
+
+/* The bootargs are populated by the previous stage bootloader */
+static const char *get_cmdline(void)
+{
+       ofnode node;
+       static const char *cmdline = NULL;
+
+       if (cmdline)
+               return cmdline;
+
+       node = ofnode_path("/chosen");
+       if (!ofnode_valid(node))
+               return NULL;
+
+       cmdline = ofnode_read_string(node, "bootargs");
+
+       return cmdline;
+}
+
+void qcom_set_serialno(void)
+{
+       const char *cmdline = get_cmdline();
+       char serial[32];
+
+       if (!cmdline) {
+               log_debug("Failed to get bootargs\n");
+               return;
+       }
+
+       get_cmdline_option(cmdline, "androidboot.serialno=", serial, sizeof(serial));
+       if (serial[0] != '\0')
+               env_set("serial#", serial);
+}
+
 /* Sets up the "board", and "soc" environment variables as well as constructing the devicetree
  * path, with a few quirks to handle non-standard dtb filenames. This is not meant to be a
  * comprehensive solution to automatically picking the DTB, but aims to be correct for the
@@ -342,6 +402,8 @@ static void configure_env(void)
        snprintf(dt_path, sizeof(dt_path), "qcom/%s-%s.dtb",
                 env_get("soc"), env_get("board"));
        env_set("fdtfile", dt_path);
+
+       qcom_set_serialno();
 }
 
 void __weak qcom_late_init(void)