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| author | Vineet Gupta <vgupta@synopsys.com> | 2015-03-09 19:40:09 +0530 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2015-06-19 18:09:27 +0530 |
| commit | 036b2c5664281e7da5a89c9f742491f30966485f (patch) | |
| tree | e9e75a0b1eac449927c2bae6a9c6887fdb22bcd3 /arch/arc | |
| parent | fd1557923b2e45a7ff4664bd88311d8239d69ca9 (diff) | |
| download | linux-036b2c5664281e7da5a89c9f742491f30966485f.tar.bz2 | |
ARC: explicit'ify uboot support
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc')
| -rw-r--r-- | arch/arc/Kconfig | 12 | ||||
| -rw-r--r-- | arch/arc/kernel/head.S | 2 | ||||
| -rw-r--r-- | arch/arc/kernel/setup.c | 5 |
3 files changed, 18 insertions, 1 deletions
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 824065a94b37..b52f7eba6765 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -388,6 +388,18 @@ config ARC_DBG_TLB_MISS_COUNT Counts number of I and D TLB Misses and exports them via Debugfs The counters can be cleared via Debugfs as well +config ARC_UBOOT_SUPPORT + bool "Support uboot arg Handling" + default n + help + ARC Linux by default checks for uboot provided args as pointers to + external cmdline or DTB. This however breaks in absence of uboot, + when booting from Metaware debugger directly, as the registers are + not zeroed out on reset by mdb and/or ARCv2 based cores. The bogus + registers look like uboot args to kernel which then chokes. + So only enable the uboot arg checking/processing if users are sure + of uboot being in play. + config ARC_BUILTIN_DTB_NAME string "Built in DTB" help diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S index b0e8666fdccc..64a92e0b1e53 100644 --- a/arch/arc/kernel/head.S +++ b/arch/arc/kernel/head.S @@ -83,6 +83,7 @@ stext: st.ab 0, [r5, 4] 1: +#ifdef CONFIG_ARC_UBOOT_SUPPORT ; Uboot - kernel ABI ; r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2 ; r1 = magic number (board identity, unused as of now @@ -90,6 +91,7 @@ stext: ; These are handled later in setup_arch() st r0, [@uboot_tag] st r2, [@uboot_arg] +#endif ; setup "current" tsk and optionally cache it in dedicated r25 mov r9, @init_task diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c index 5086c75681b5..c6e8b72ff293 100644 --- a/arch/arc/kernel/setup.c +++ b/arch/arc/kernel/setup.c @@ -319,13 +319,16 @@ static inline int is_kernel(unsigned long addr) void __init setup_arch(char **cmdline_p) { +#ifdef CONFIG_ARC_UBOOT_SUPPORT /* make sure that uboot passed pointer to cmdline/dtb is valid */ if (uboot_tag && is_kernel((unsigned long)uboot_arg)) panic("Invalid uboot arg\n"); /* See if u-boot passed an external Device Tree blob */ machine_desc = setup_machine_fdt(uboot_arg); /* uboot_tag == 2 */ - if (!machine_desc) { + if (!machine_desc) +#endif + { /* No, so try the embedded one */ machine_desc = setup_machine_fdt(__dtb_start); if (!machine_desc) |