From 4da019edeb62154978dfac6a37e738814b2f2724 Mon Sep 17 00:00:00 2001 From: ntfreak Date: Tue, 21 Jul 2009 20:15:11 +0000 Subject: David Brownell : Clean up treatment of registers in ARMv7-M and Cortex-M3. - At the arch level: * Just list registers and names; don't impose core-specific policy about how they are accessed. * Each register has a symbol. * Remove the register mode field (irrelevant to debugger) - At the core/implementation level: * Just map the registers to their relevant access methods; don't require the arch level to say how that should work (cores other than Cortex-M3 could do it differently). * Don't use undefined bits from register 20. * Use register IDs that are part of the ARMv7-M interface. In short, there's now a real distinction between the arch and core layers. git-svn-id: svn://svn.berlios.de/openocd/trunk@2554 b42882b7-edfa-0310-969c-e2dbd0fdcd60 --- src/target/cortex_m3.c | 103 ++++++++++++++++++++++++++++--------------------- 1 file changed, 59 insertions(+), 44 deletions(-) (limited to 'src/target/cortex_m3.c') diff --git a/src/target/cortex_m3.c b/src/target/cortex_m3.c index 94d42046..8875dddc 100644 --- a/src/target/cortex_m3.c +++ b/src/target/cortex_m3.c @@ -395,7 +395,9 @@ int cortex_m3_debug_entry(target_t *target) /* Examine target state and mode */ /* First load register acessible through core debug port*/ - for (i = 0; i < ARMV7M_PRIMASK; i++) + int num_regs = armv7m->core_cache->num_regs; + + for (i = 0; i < num_regs; i++) { if (!armv7m->core_cache->reg_list[i].valid) armv7m->read_core_reg(target, i); @@ -418,13 +420,6 @@ int cortex_m3_debug_entry(target_t *target) cortex_m3_store_core_reg_u32(target, ARMV7M_REGISTER_CORE_GP, 16, xPSR &~ 0xff); } - /* Now we can load SP core registers */ - for (i = ARMV7M_PRIMASK; i < ARMV7NUMCOREREGS; i++) - { - if (!armv7m->core_cache->reg_list[i].valid) - armv7m->read_core_reg(target, i); - } - /* Are we in an exception handler */ if (xPSR & 0x1FF) { @@ -1253,8 +1248,12 @@ int cortex_m3_load_core_reg_u32(struct target_s *target, enum armv7m_regtype typ armv7m_common_t *armv7m = target->arch_info; swjdp_common_t *swjdp = &armv7m->swjdp_info; - if ((type == ARMV7M_REGISTER_CORE_GP) && (num <= ARMV7M_PSP)) - { + /* NOTE: we "know" here that the register identifiers used + * in the v7m header match the Cortex-M3 Debug Core Register + * Selector values for R0..R15, xPSR, MSP, and PSP. + */ + switch (num) { + case 0 ... 18: /* read a normal core register */ retval = cortexm3_dap_read_coreregister_u32(swjdp, value, num); @@ -1264,35 +1263,41 @@ int cortex_m3_load_core_reg_u32(struct target_s *target, enum armv7m_regtype typ return ERROR_JTAG_DEVICE_ERROR; } LOG_DEBUG("load from core reg %i value 0x%" PRIx32 "",(int)num,*value); - } - else if (type == ARMV7M_REGISTER_CORE_SP) /* Special purpose core register */ - { - /* read other registers */ + break; + + case ARMV7M_PRIMASK: + case ARMV7M_BASEPRI: + case ARMV7M_FAULTMASK: + case ARMV7M_CONTROL: + /* Cortex-M3 packages these four registers as bitfields + * in one Debug Core register. So say r0 and r2 docs; + * it was removed from r1 docs, but still works. + */ cortexm3_dap_read_coreregister_u32(swjdp, value, 20); switch (num) { - case 19: - *value = buf_get_u32((uint8_t*)value, 0, 8); + case ARMV7M_PRIMASK: + *value = buf_get_u32((uint8_t*)value, 0, 1); break; - case 20: + case ARMV7M_BASEPRI: *value = buf_get_u32((uint8_t*)value, 8, 8); break; - case 21: - *value = buf_get_u32((uint8_t*)value, 16, 8); + case ARMV7M_FAULTMASK: + *value = buf_get_u32((uint8_t*)value, 16, 1); break; - case 22: - *value = buf_get_u32((uint8_t*)value, 24, 8); + case ARMV7M_CONTROL: + *value = buf_get_u32((uint8_t*)value, 24, 2); break; } LOG_DEBUG("load from special reg %i value 0x%" PRIx32 "", (int)num, *value); - } - else - { + break; + + default: return ERROR_INVALID_ARGUMENTS; } @@ -1313,14 +1318,19 @@ int cortex_m3_store_core_reg_u32(struct target_s *target, enum armv7m_regtype ty * in "thumb" mode, or an INVSTATE exception will occur. This is a * hack to deal with the fact that gdb will sometimes "forge" * return addresses, and doesn't set the LSB correctly (i.e., when - * printing expressions containing function calls, it sets LR = 0.) */ - - if (num == 14) + * printing expressions containing function calls, it sets LR = 0.) + * Valid exception return codes have bit 0 set too. + */ + if (num == ARMV7M_R14) value |= 0x01; #endif - if ((type == ARMV7M_REGISTER_CORE_GP) && (num <= ARMV7M_PSP)) - { + /* NOTE: we "know" here that the register identifiers used + * in the v7m header match the Cortex-M3 Debug Core Register + * Selector values for R0..R15, xPSR, MSP, and PSP. + */ + switch (num) { + case 0 ... 18: retval = cortexm3_dap_write_coreregister_u32(swjdp, value, num); if (retval != ERROR_OK) { @@ -1329,38 +1339,43 @@ int cortex_m3_store_core_reg_u32(struct target_s *target, enum armv7m_regtype ty return ERROR_JTAG_DEVICE_ERROR; } LOG_DEBUG("write core reg %i value 0x%" PRIx32 "", (int)num, value); - } - else if (type == ARMV7M_REGISTER_CORE_SP) /* Special purpose core register */ - { - /* write other registers */ - + break; + + case ARMV7M_PRIMASK: + case ARMV7M_BASEPRI: + case ARMV7M_FAULTMASK: + case ARMV7M_CONTROL: + /* Cortex-M3 packages these four registers as bitfields + * in one Debug Core register. So say r0 and r2 docs; + * it was removed from r1 docs, but still works. + */ cortexm3_dap_read_coreregister_u32(swjdp, ®, 20); switch (num) { - case 19: - buf_set_u32((uint8_t*)®, 0, 8, value); + case ARMV7M_PRIMASK: + buf_set_u32((uint8_t*)®, 0, 1, value); break; - case 20: + case ARMV7M_BASEPRI: buf_set_u32((uint8_t*)®, 8, 8, value); break; - case 21: - buf_set_u32((uint8_t*)®, 16, 8, value); + case ARMV7M_FAULTMASK: + buf_set_u32((uint8_t*)®, 16, 1, value); break; - case 22: - buf_set_u32((uint8_t*)®, 24, 8, value); + case ARMV7M_CONTROL: + buf_set_u32((uint8_t*)®, 24, 2, value); break; } cortexm3_dap_write_coreregister_u32(swjdp, reg, 20); LOG_DEBUG("write special reg %i value 0x%" PRIx32 " ", (int)num, value); - } - else - { + break; + + default: return ERROR_INVALID_ARGUMENTS; } -- cgit v1.2.3