Introduce a new (global, sorry!) option which controls whether

the ar71xx platform code should assume a uboot or redboot environment.

The current code gets very confused (and just crashes) on a uboot
environment, where each attribute=value pair is in a single entry.
Redboot on the other hand stores it as "attribute", "value", "attribute",
"value", ...

This allows the kernel to boot on a TP-LINK TL-WR1043ND from flash,
where the uboot environment gets setup. This didn't show up during a netboot
as "tftpboot" and "go" don't setup the uboot environment variables.

2 files changed, 16 insertions, 3 deletions

diff --git a/sys/conf/options b/sys/conf/options
index 12e676e..12dbc81 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -899,4 +899,5 @@ RCTL		opt_global.h
 # that "lies" about the amount of RAM it has. Until a cleaner method is
 # defined, this option will suffice in overriding what Redboot says.
 AR71XX_REALMEM    opt_global.h
-
+AR71XX_ENV_UBOOT	opt_global.h
+AR71XX_ENV_REDBOOT	opt_global.h
diff --git a/sys/mips/atheros/ar71xx_machdep.c b/sys/mips/atheros/ar71xx_machdep.c
index 1789994..bcb5807 100644
--- a/sys/mips/atheros/ar71xx_machdep.c
+++ b/sys/mips/atheros/ar71xx_machdep.c
@@ -168,8 +168,8 @@ platform_start(__register_t a0 __unused, __register_t a1 __unused,
     __register_t a2 __unused, __register_t a3 __unused)
 {
 	uint64_t platform_counter_freq;
-	int argc, i;
-	char **argv, **envp;
+	int argc = 0, i;
+	char **argv = NULL, **envp = NULL;
 	vm_offset_t kernend;
 
 	/* 
@@ -184,9 +184,18 @@ platform_start(__register_t a0 __unused, __register_t a1 __unused,
 	/* Initialize pcpu stuff */
 	mips_pcpu0_init();
 
+	/*
+	 * Until some more sensible abstractions for uboot/redboot
+	 * environment handling, we have to make this a compile-time
+	 * hack.  The existing code handles the uboot environment
+	 * very incorrectly so we should just ignore initialising
+	 * the relevant pointers.
+	 */
+#ifndef	AR71XX_ENV_UBOOT
 	argc = a0;
 	argv = (char**)a1;
 	envp = (char**)a2;
+#endif
 	/* 
 	 * Protect ourselves from garbage in registers 
 	 */
@@ -255,6 +264,9 @@ platform_start(__register_t a0 __unused, __register_t a1 __unused,
 	printf("  a2 = %08x\n", a2);
 	printf("  a3 = %08x\n", a3);
 
+	/*
+	 * XXX this code is very redboot specific.
+	 */
 	printf("Cmd line:");
 	if (MIPS_IS_VALID_PTR(argv)) {
 		for (i = 0; i < argc; i++) {