From adc421e4cee8275cd99367b3b455ffbb5ead3990 Mon Sep 17 00:00:00 2001 From: Albert ARIBAUD Date: Wed, 25 Nov 2015 17:56:33 +0100 Subject: arm: move gd handling outside of C code As of gcc 5.2.1 for Thumb-1, it is not possible any more to assign gd from C code, as gd is mapped to r9, and r9 may now be saved in the prolog sequence, and restored in the epilog sequence, of any C functions. Therefore arch_setup_gd(), which is supposed to set r9, may actually have no effect, causing U-Boot to use a bad address to access GD. Fix this by never calling arch_setup_gd() for ARM, and instead setting r9 in arch/arm/lib/crt0.S, to the value returned by board_init_f_alloc_reserve(). Signed-off-by: Albert ARIBAUD Reviewed-by: Simon Glass --- common/spl/spl.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) (limited to 'common/spl') diff --git a/common/spl/spl.c b/common/spl/spl.c index 6e6dee7..e5167bf 100644 --- a/common/spl/spl.c +++ b/common/spl/spl.c @@ -431,8 +431,13 @@ void preloader_console_init(void) * more stack space for things like the MMC sub-system. * * This function calculates the stack position, copies the global_data into - * place and returns the new stack position. The caller is responsible for - * setting up the sp register. + * place, sets the new gd (except for ARM, for which setting GD within a C + * function may not always work) and returns the new stack position. The + * caller is responsible for setting up the sp register and, in the case + * of ARM, setting up gd. + * + * All of this is done using the same layout and alignments as done in + * board_init_f_init_reserve() / board_init_f_alloc_reserve(). * * @return new stack location, or 0 to use the same stack */ @@ -440,14 +445,7 @@ ulong spl_relocate_stack_gd(void) { #ifdef CONFIG_SPL_STACK_R gd_t *new_gd; - ulong ptr; - - /* Get stack position: use 8-byte alignment for ABI compliance */ - ptr = CONFIG_SPL_STACK_R_ADDR - sizeof(gd_t); - ptr &= ~7; - new_gd = (gd_t *)ptr; - memcpy(new_gd, (void *)gd, sizeof(gd_t)); - gd = new_gd; + ulong ptr = CONFIG_SPL_STACK_R_ADDR; #ifdef CONFIG_SPL_SYS_MALLOC_SIMPLE if (CONFIG_SPL_STACK_R_MALLOC_SIMPLE_LEN) { @@ -460,7 +458,13 @@ ulong spl_relocate_stack_gd(void) gd->malloc_ptr = 0; } #endif - + /* Get stack position: use 8-byte alignment for ABI compliance */ + ptr = CONFIG_SPL_STACK_R_ADDR - roundup(sizeof(gd_t),16); + new_gd = (gd_t *)ptr; + memcpy(new_gd, (void *)gd, sizeof(gd_t)); +#if !defined(CONFIG_ARM) + gd = new_gd; +#endif return ptr; #else return 0; -- cgit v1.1