ipq: fdt_fixup: Add support to change dts params using env

The env name should "fdtedit" followed by number from 0.
example: fdtedit0, fdtedit1, fdtedit2, ...

Set the number of envs to parse, "setenv fdteditnum <number>"
<number> can be between 1 to 99. eg: "setenv fdteditnum 5"

Without setting 'fdteditnum' fdtedit envs will not parsed.

To change add/change a particular property of a node:
setenv fdtedit0 <node_path>%<property>%<value>
example:
fdtedit0=/soc/qca,scm_restart_reason%qca,coldreboot-enabled%1
fdtedit1=/soc/usb3@8A00000/dwc3@8A00000%dr_mode%?peripheral

To delete a property of a node:
setenv fdtedit0 <node_path>%delete%<property>
example:
fdtedit2=/soc/q6v5_wcss@CD00000%delete%?qca,secure

The last param in both case, if it is a string, it should
start with '?' else if it is a number, it can be put directly.
check above examples for reference.

Change-Id: Ib22ec8098925b49b013bc115f11e043bf8ab3ef5
Signed-off-by: Balaji Prakash J <bjagadee@codeaurora.org>

board/qca/arm/common/fdt_fixup.c

@@ -19,6 +19,11 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#ifdef CONFIG_IPQ_FDT_FIXUP
+#define FDT_EDIT "fdtedit"
+/* Buffer size to hold numbers from 0-99 + 1 NULL character */
+#define NUM_BUF_SIZE 3
+#endif
 /*
  * Don't have this as a '.bss' variable. The '.bss' and '.rel.dyn'
  * sections seem to overlap.
@@ -481,6 +486,91 @@ static int ipq40xx_patch_eth_params(void *blob, unsigned long gmac_no)
 	return 0;
 }
 
+#ifdef CONFIG_IPQ_FDT_FIXUP
+void parse_fdt_fixup(char* buf, void *blob)
+{
+	int nodeoff, value, ret;
+	char *node, *property, *node_value;
+	bool str = true;
+
+	node = strsep(&buf, "%");
+	property = strsep(&buf, "%");
+	node_value = strsep(&buf, "%");
+
+	debug("node: %s, property: %s, node_value: %s\n",
+			node, property, node_value);
+
+	if (node_value && node_value[0] != '?') {
+		str = false;
+		value = simple_strtoul(node_value, NULL, 10);
+	} else {
+		node_value++;
+	}
+
+	nodeoff = fdt_path_offset(blob, node);
+	if (nodeoff < 0) {
+		printf("%s: unable to find node '%s'\n",
+				__func__, node);
+		return;
+	}
+
+	if (!strncmp(property, "delete", strlen("delete"))) {
+		ret = fdt_delprop(blob, nodeoff, node_value);
+		if (ret) {
+			printf("%s: unable to delete %s\n",
+					__func__, node_value);
+			return;
+		}
+	} else if (!str) {
+		ret = fdt_setprop_u32(blob, nodeoff, property,
+				value);
+		if (ret) {
+			printf("%s: failed to set prop %s\n",
+					__func__, property);
+			return;
+		}
+	} else {
+		ret = fdt_setprop(blob, nodeoff, property,
+				node_value,
+				(strlen(node_value) + 1));
+		if (ret) {
+			printf("%s: failed to set prop %s\n",
+					__func__, property);
+			return;
+		}
+	}
+}
+
+void ipq_fdt_fixup(void *blob)
+{
+	int i, fdteditnum;
+	char buf[sizeof(FDT_EDIT) + NUM_BUF_SIZE], num[NUM_BUF_SIZE];
+	char *s;
+
+	/* fdteditnum - defines the number of envs to parse
+	 * starting from 0. eg: fdtedit0, fdtedit1, and so on.
+	 */
+	s = getenv("fdteditnum");
+	if (s)
+		fdteditnum = simple_strtoul(s, NULL, 10);
+	else
+		return;
+
+	printf("%s: fixup fdtedits\n", __func__);
+
+	for (i = 0; i <= fdteditnum; i++) {
+		/* Generate env names fdtedit0, fdtedit1,..fdteditn */
+		strlcpy(buf, FDT_EDIT, sizeof(buf));
+		snprintf(num, sizeof(num), "%d", i);
+		strlcat(buf, num, sizeof(buf));
+
+		s = getenv(buf);
+		if (s)
+			parse_fdt_fixup(s, blob);
+	}
+}
+#endif
+
 __weak void fdt_fixup_sd_ldo_gpios_toggle(void *blob)
 {
 	return;
@@ -616,6 +706,9 @@ int ft_board_setup(void *blob, bd_t *bd)
 			ipq40xx_patch_eth_params(blob, gmac_no);
 	}
 	dcache_disable();
+#ifdef CONFIG_IPQ_FDT_FIXUP
+	ipq_fdt_fixup(blob);
+#endif
 	fdt_fixup_ethernet(blob);
 	ipq_fdt_fixup_usb_device_mode(blob);
 	fdt_fixup_auto_restart(blob);

include/common.h

@@ -359,6 +359,8 @@ void board_show_dram(phys_size_t size);
  */
 int arch_fixup_fdt(void *blob);
 
+void parse_fdt_fixup(char* buf, void *blob);
+
 /* common/flash.c */
 void flash_perror (int);
 

include/configs/ipq6018.h

@@ -362,5 +362,6 @@ extern loff_t board_env_size;
 #define CONFIG_IPQ_ELF_AUTH
 #define IPQ_UBI_VOL_WRITE_SUPPORT
 #define CONFIG_IPQ_TZT
+#define CONFIG_IPQ_FDT_FIXUP
 
 #endif /* _IPQ6018_H */