From 45c7498f59ad2889f2120a865a51043004eddd5d Mon Sep 17 00:00:00 2001 From: Rafaël Carré Date: Fri, 11 Jun 2010 04:41:36 +0000 Subject: FS#11335 by me: make ARM assembly functions thumb-friendly We can't pop into pc on ARMv4t when using thumb: the T bit won't be modified if we are returning to a thumb function Code running on ARMv4t should use the new ldrpc / ldmpc macros instead of ldr pc, [sp], #4 and ldm(cond) sp!, {regs, pc} No modification on pure ARM builds and ARMv5+ Note: USE_THUMB is currently never defined, no targets can currently be built with -mthumb, see FS#6734 git-svn-id: svn://svn.rockbox.org/rockbox/trunk@26756 a1c6a512-1295-4272-9138-f99709370657 --- firmware/target/arm/thread-arm.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'firmware/target/arm/thread-arm.c') diff --git a/firmware/target/arm/thread-arm.c b/firmware/target/arm/thread-arm.c index c2d91cec25..9ea3d0bef9 100644 --- a/firmware/target/arm/thread-arm.c +++ b/firmware/target/arm/thread-arm.c @@ -77,7 +77,15 @@ static inline void load_context(const void* addr) asm volatile( "ldr r0, [%0, #40] \n" /* Load start pointer */ "cmp r0, #0 \n" /* Check for NULL */ - "ldmneia %0, { r0, pc } \n" /* If not already running, jump to start */ + + /* If not already running, jump to start */ +#if ARM_ARCH == 4 && defined(USE_THUMB) + "ldmneia %0, { r0, r12 } \n" + "bxne r12 \n" +#else + "ldmneia %0, { r0, pc } \n" +#endif + "ldmia %0, { r4-r11, sp, lr } \n" /* Load regs r4 to r14 from context */ : : "r" (addr) : "r0" /* only! */ ); -- cgit v1.2.3