From da7c202b5751c1420be6725c6eb456a2f723ba74 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Mon, 30 Nov 2009 19:14:19 -0800 Subject: XScale: context restore, cleanup/bugfix This "loop over all registers" routine shared the same mess as full_context() in terms of dozens of needless number_to_mode() calls. Fix that, and comments, with related cleanup. The misnamed xscale_restore_context() had a related bug. It was restoring the *WRONG REGISTERS* ... always from whatever the current mode was, instead of using the copy from whichever register bank it was trying to restore. (But it marked the intended register as having been restored...) Fixed that. Signed-off-by: David Brownell --- src/target/xscale.c | 44 +++++++++++++++++++++++++++++--------------- 1 file changed, 29 insertions(+), 15 deletions(-) (limited to 'src/target') diff --git a/src/target/xscale.c b/src/target/xscale.c index bf5d0afa..0680c520 100644 --- a/src/target/xscale.c +++ b/src/target/xscale.c @@ -1768,37 +1768,45 @@ static int xscale_restore_context(struct target *target) } /* iterate through processor modes (FIQ, IRQ, SVC, ABT, UND and SYS) - * we can't enter User mode on an XScale (unpredictable), - * but User shares registers with SYS - */ + * and check if any banked registers need to be written. Ignore + * USR mode (number 0) in favor of SYS; we can't enter User mode on + * an XScale (unpredictable), but they share all registers. + */ for (i = 1; i < 7; i++) { int dirty = 0; + enum armv4_5_mode mode = armv4_5_number_to_mode(i); - /* check if there are invalid registers in the current mode - */ + if (mode == ARMV4_5_MODE_USR) + continue; + + /* check if there are dirty registers in this mode */ for (j = 8; j <= 14; j++) { - if (ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, armv4_5_number_to_mode(i), j).dirty == 1) + if (ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, + mode, j).dirty) dirty = 1; } /* if not USR/SYS, check if the SPSR needs to be written */ - if ((armv4_5_number_to_mode(i) != ARMV4_5_MODE_USR) && (armv4_5_number_to_mode(i) != ARMV4_5_MODE_SYS)) + if (mode != ARMV4_5_MODE_SYS) { - if (ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, armv4_5_number_to_mode(i), 16).dirty == 1) + if (ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, + mode, 16).dirty) dirty = 1; } + /* is there anything to flush for this mode? */ if (dirty) { uint32_t tmp_cpsr; + struct reg *r; - /* send banked registers */ + /* command 0x1: "send banked registers" */ xscale_send_u32(target, 0x1); tmp_cpsr = 0x0; - tmp_cpsr |= armv4_5_number_to_mode(i); + tmp_cpsr |= mode; tmp_cpsr |= 0xc0; /* I/F bits */ /* send CPSR for desired mode */ @@ -1807,14 +1815,20 @@ static int xscale_restore_context(struct target *target) /* send banked registers, r8 to r14, and spsr if not in USR/SYS mode */ for (j = 8; j <= 14; j++) { - xscale_send_u32(target, buf_get_u32(ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, armv4_5->core_mode, j).value, 0, 32)); - ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, armv4_5_number_to_mode(i), j).dirty = 0; + r = &ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, + mode, j); + xscale_send_u32(target, + buf_get_u32(r->value, 0, 32)); + r->dirty = false; } - if ((armv4_5_number_to_mode(i) != ARMV4_5_MODE_USR) && (armv4_5_number_to_mode(i) != ARMV4_5_MODE_SYS)) + if (mode != ARMV4_5_MODE_SYS) { - xscale_send_u32(target, buf_get_u32(ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, armv4_5->core_mode, 16).value, 0, 32)); - ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, armv4_5_number_to_mode(i), 16).dirty = 0; + r = &ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, + mode, 16); + xscale_send_u32(target, + buf_get_u32(r->value, 0, 32)); + r->dirty = false; } } } -- cgit v1.2.3