cortex: autostep correctly handle user breakpoint
[fw/openocd] / src / target / cortex_m.c
index 76e197c116d904fe8c2fb046138b818363986f12..4d9daf5ca09e48de924fda94476f4b207655107d 100644 (file)
@@ -31,6 +31,7 @@
 #include "config.h"
 #endif
 
+#include "jtag/interface.h"
 #include "breakpoints.h"
 #include "cortex_m.h"
 #include "target_request.h"
@@ -148,7 +149,7 @@ static int cortex_m3_write_debug_halt_mask(struct target *target,
        uint32_t mask_on, uint32_t mask_off)
 {
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
-       struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
+       struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 
        /* mask off status bits */
        cortex_m3->dcb_dhcsr &= ~((0xFFFF << 16) | mask_off);
@@ -161,7 +162,7 @@ static int cortex_m3_write_debug_halt_mask(struct target *target,
 static int cortex_m3_clear_halt(struct target *target)
 {
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
-       struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
+       struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
        int retval;
 
        /* clear step if any */
@@ -184,7 +185,7 @@ static int cortex_m3_clear_halt(struct target *target)
 static int cortex_m3_single_step_core(struct target *target)
 {
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
-       struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
+       struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
        uint32_t dhcsr_save;
        int retval;
 
@@ -221,7 +222,7 @@ static int cortex_m3_endreset_event(struct target *target)
        uint32_t dcb_demcr;
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
        struct armv7m_common *armv7m = &cortex_m3->armv7m;
-       struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
+       struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
        struct cortex_m3_fp_comparator *fp_list = cortex_m3->fp_comparator_list;
        struct cortex_m3_dwt_comparator *dwt_list = cortex_m3->dwt_comparator_list;
 
@@ -333,7 +334,7 @@ static int cortex_m3_examine_exception_reason(struct target *target)
 {
        uint32_t shcsr = 0, except_sr = 0, cfsr = -1, except_ar = -1;
        struct armv7m_common *armv7m = target_to_armv7m(target);
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
        int retval;
 
        retval = mem_ap_read_u32(swjdp, NVIC_SHCSR, &shcsr);
@@ -405,7 +406,7 @@ static int cortex_m3_debug_entry(struct target *target)
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
        struct armv7m_common *armv7m = &cortex_m3->armv7m;
        struct arm *arm = &armv7m->arm;
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
        struct reg *r;
 
        LOG_DEBUG(" ");
@@ -497,7 +498,7 @@ static int cortex_m3_poll(struct target *target)
        int retval = ERROR_OK;
        enum target_state prev_target_state = target->state;
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
-       struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
+       struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 
        /* Read from Debug Halting Control and Status Register */
        retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
@@ -628,7 +629,7 @@ static int cortex_m3_halt(struct target *target)
 static int cortex_m3_soft_reset_halt(struct target *target)
 {
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
-       struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
+       struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
        uint32_t dcb_dhcsr = 0;
        int retval, timeout = 0;
 
@@ -793,7 +794,7 @@ static int cortex_m3_step(struct target *target, int current,
 {
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
        struct armv7m_common *armv7m = &cortex_m3->armv7m;
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
        struct breakpoint *breakpoint = NULL;
        struct reg *pc = armv7m->arm.pc;
        bool bkpt_inst_found = false;
@@ -853,45 +854,78 @@ static int cortex_m3_step(struct target *target, int current,
                         *
                         */
 
-                       /* Set a temporary break point */
-                       retval = breakpoint_add(target, pc_value, 2, BKPT_TYPE_BY_ADDR(pc_value));
-                       bool tmp_bp_set = (retval == ERROR_OK);
-
-                       /* No more breakpoints left, just do a step */
-                       if (!tmp_bp_set)
+                       /* 2012-09-29 ph
+                        *
+                        * If a break point is already set on the lower half word then a break point on
+                        * the upper half word will not break again when the core is restarted. So we
+                        * just step over the instruction with interrupts disabled.
+                        *
+                        * The documentation has no information about this, it was found by observation
+                        * on STM32F1 and STM32F2. Proper explanation welcome. STM32F0 dosen't seem to
+                        * suffer from this problem.
+                        *
+                        * To add some confusion: pc_value has bit 0 always set, while the breakpoint
+                        * address has it always cleared. The former is done to indicate thumb mode
+                        * to gdb.
+                        *
+                        */
+                       if ((pc_value & 0x02) && breakpoint_find(target, pc_value & ~0x03)) {
+                               LOG_DEBUG("Stepping over next instruction with interrupts disabled");
+                               cortex_m3_write_debug_halt_mask(target, C_HALT | C_MASKINTS, 0);
                                cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
+                               /* Re-enable interrupts */
+                               cortex_m3_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
+                       }
                        else {
-                               /* Start the core */
-                               LOG_DEBUG("Starting core to serve pending interrupts");
-                               int64_t t_start = timeval_ms();
-                               cortex_m3_write_debug_halt_mask(target, 0, C_HALT | C_STEP);
-
-                               /* Wait for pending handlers to complete or timeout */
-                               do {
-                                       retval = mem_ap_read_atomic_u32(swjdp,
-                                                       DCB_DHCSR,
-                                                       &cortex_m3->dcb_dhcsr);
-                                       if (retval != ERROR_OK) {
-                                               target->state = TARGET_UNKNOWN;
-                                               return retval;
-                                       }
-                                       isr_timed_out = ((timeval_ms() - t_start) > 500);
-                               } while (!((cortex_m3->dcb_dhcsr & S_HALT) || isr_timed_out));
-
-                               /* Remove the temporary breakpoint */
-                               breakpoint_remove(target, pc_value);
-
-                               if (isr_timed_out) {
-                                       LOG_DEBUG("Interrupt handlers didn't complete within time, "
-                                               "leaving target running");
-                               } else {
-                                       /* Step over next instruction with interrupts disabled */
-                                       cortex_m3_write_debug_halt_mask(target,
-                                               C_HALT | C_MASKINTS,
-                                               0);
+
+                               /* Set a temporary break point */
+                               if (breakpoint)
+                                       retval = cortex_m3_set_breakpoint(target, breakpoint);
+                               else
+                                       retval = breakpoint_add(target, pc_value, 2, BKPT_TYPE_BY_ADDR(pc_value));
+                               bool tmp_bp_set = (retval == ERROR_OK);
+
+                               /* No more breakpoints left, just do a step */
+                               if (!tmp_bp_set)
                                        cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
-                                       /* Re-enable interrupts */
-                                       cortex_m3_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
+                               else {
+                                       /* Start the core */
+                                       LOG_DEBUG("Starting core to serve pending interrupts");
+                                       int64_t t_start = timeval_ms();
+                                       cortex_m3_write_debug_halt_mask(target, 0, C_HALT | C_STEP);
+
+                                       /* Wait for pending handlers to complete or timeout */
+                                       do {
+                                               retval = mem_ap_read_atomic_u32(swjdp,
+                                                               DCB_DHCSR,
+                                                               &cortex_m3->dcb_dhcsr);
+                                               if (retval != ERROR_OK) {
+                                                       target->state = TARGET_UNKNOWN;
+                                                       return retval;
+                                               }
+                                               isr_timed_out = ((timeval_ms() - t_start) > 500);
+                                       } while (!((cortex_m3->dcb_dhcsr & S_HALT) || isr_timed_out));
+
+                                       /* only remove breakpoint if we created it */
+                                       if (breakpoint)
+                                               cortex_m3_unset_breakpoint(target, breakpoint);
+                                       else {
+                                               /* Remove the temporary breakpoint */
+                                               breakpoint_remove(target, pc_value);
+                                       }
+
+                                       if (isr_timed_out) {
+                                               LOG_DEBUG("Interrupt handlers didn't complete within time, "
+                                                       "leaving target running");
+                                       } else {
+                                               /* Step over next instruction with interrupts disabled */
+                                               cortex_m3_write_debug_halt_mask(target,
+                                                       C_HALT | C_MASKINTS,
+                                                       0);
+                                               cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
+                                               /* Re-enable interrupts */
+                                               cortex_m3_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
+                                       }
                                }
                        }
                }
@@ -933,7 +967,7 @@ static int cortex_m3_step(struct target *target, int current,
 static int cortex_m3_assert_reset(struct target *target)
 {
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
-       struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
+       struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
        enum cortex_m3_soft_reset_config reset_config = cortex_m3->soft_reset_config;
 
        LOG_DEBUG("target->state: %s",
@@ -951,6 +985,16 @@ static int cortex_m3_assert_reset(struct target *target)
                return ERROR_OK;
        }
 
+       /* some cores support connecting while srst is asserted
+        * use that mode is it has been configured */
+
+       bool srst_asserted = false;
+
+       if (jtag_reset_config & RESET_SRST_NO_GATING) {
+               adapter_assert_reset();
+               srst_asserted = true;
+       }
+
        /* Enable debug requests */
        int retval;
        retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
@@ -962,6 +1006,14 @@ static int cortex_m3_assert_reset(struct target *target)
                        return retval;
        }
 
+       /* If the processor is sleeping in a WFI or WFE instruction, the
+        * C_HALT bit must be asserted to regain control */
+       if (cortex_m3->dcb_dhcsr & S_SLEEP) {
+               retval = mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_HALT | C_DEBUGEN);
+               if (retval != ERROR_OK)
+                       return retval;
+       }
+
        retval = mem_ap_write_u32(swjdp, DCB_DCRDR, 0);
        if (retval != ERROR_OK)
                return retval;
@@ -995,10 +1047,8 @@ static int cortex_m3_assert_reset(struct target *target)
 
        if (jtag_reset_config & RESET_HAS_SRST) {
                /* default to asserting srst */
-               if (jtag_reset_config & RESET_SRST_PULLS_TRST)
-                       jtag_add_reset(1, 1);
-               else
-                       jtag_add_reset(0, 1);
+               if (!srst_asserted)
+                       adapter_assert_reset();
        } else {
                /* Use a standard Cortex-M3 software reset mechanism.
                 * We default to using VECRESET as it is supported on all current cores.
@@ -1016,7 +1066,7 @@ static int cortex_m3_assert_reset(struct target *target)
 
                if (reset_config == CORTEX_M3_RESET_VECTRESET) {
                        LOG_WARNING("Only resetting the Cortex-M3 core, use a reset-init event "
-                               "handler to reset any peripherals");
+                               "handler to reset any peripherals or configure hardware srst support.");
                }
 
                {
@@ -1051,7 +1101,7 @@ static int cortex_m3_deassert_reset(struct target *target)
                target_state_name(target));
 
        /* deassert reset lines */
-       jtag_add_reset(0, 0);
+       adapter_deassert_reset();
 
        return ERROR_OK;
 }
@@ -1420,7 +1470,7 @@ static int cortex_m3_load_core_reg_u32(struct target *target,
 {
        int retval;
        struct armv7m_common *armv7m = target_to_armv7m(target);
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
 
        /* NOTE:  we "know" here that the register identifiers used
         * in the v7m header match the Cortex-M3 Debug Core Register
@@ -1482,7 +1532,7 @@ static int cortex_m3_store_core_reg_u32(struct target *target,
        int retval;
        uint32_t reg;
        struct armv7m_common *armv7m = target_to_armv7m(target);
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
 
 #ifdef ARMV7_GDB_HACKS
        /* If the LR register is being modified, make sure it will put us
@@ -1558,9 +1608,15 @@ static int cortex_m3_read_memory(struct target *target, uint32_t address,
        uint32_t size, uint32_t count, uint8_t *buffer)
 {
        struct armv7m_common *armv7m = target_to_armv7m(target);
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
        int retval = ERROR_COMMAND_SYNTAX_ERROR;
 
+       if (armv7m->arm.is_armv6m) {
+               /* armv6m does not handle unaligned memory access */
+               if (((size == 4) && (address & 0x3u)) || ((size == 2) && (address & 0x1u)))
+                       return ERROR_TARGET_UNALIGNED_ACCESS;
+       }
+
        /* cortex_m3 handles unaligned memory access */
        if (count && buffer) {
                switch (size) {
@@ -1583,9 +1639,15 @@ static int cortex_m3_write_memory(struct target *target, uint32_t address,
        uint32_t size, uint32_t count, const uint8_t *buffer)
 {
        struct armv7m_common *armv7m = target_to_armv7m(target);
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
        int retval = ERROR_COMMAND_SYNTAX_ERROR;
 
+       if (armv7m->arm.is_armv6m) {
+               /* armv6m does not handle unaligned memory access */
+               if (((size == 4) && (address & 0x3u)) || ((size == 2) && (address & 0x1u)))
+                       return ERROR_TARGET_UNALIGNED_ACCESS;
+       }
+
        if (count && buffer) {
                switch (size) {
                        case 4:
@@ -1756,17 +1818,28 @@ fail1:
         */
 }
 
+#define MVFR0 0xe000ef40
+#define MVFR1 0xe000ef44
+
+#define MVFR0_DEFAULT_M4 0x10110021
+#define MVFR1_DEFAULT_M4 0x11000011
+
 int cortex_m3_examine(struct target *target)
 {
        int retval;
-       uint32_t cpuid, fpcr;
+       uint32_t cpuid, fpcr, mvfr0, mvfr1;
        int i;
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
-       struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
+       struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
+       struct armv7m_common *armv7m = target_to_armv7m(target);
 
-       retval = ahbap_debugport_init(swjdp);
-       if (retval != ERROR_OK)
-               return retval;
+       /* stlink shares the examine handler but does not support
+        * all its calls */
+       if (!armv7m->stlink) {
+               retval = ahbap_debugport_init(swjdp);
+               if (retval != ERROR_OK)
+                       return retval;
+       }
 
        if (!target_was_examined(target)) {
                target_set_examined(target);
@@ -1783,6 +1856,25 @@ int cortex_m3_examine(struct target *target)
                                i, (uint8_t)((cpuid >> 20) & 0xf), (uint8_t)((cpuid >> 0) & 0xf));
                LOG_DEBUG("cpuid: 0x%8.8" PRIx32 "", cpuid);
 
+               /* test for floating point feature on cortex-m4 */
+               if (i == 4) {
+                       target_read_u32(target, MVFR0, &mvfr0);
+                       target_read_u32(target, MVFR1, &mvfr1);
+
+                       if ((mvfr0 == MVFR0_DEFAULT_M4) && (mvfr1 == MVFR1_DEFAULT_M4)) {
+                               LOG_DEBUG("Cortex-M%d floating point feature FPv4_SP found", i);
+                               armv7m->fp_feature = FPv4_SP;
+                       }
+               } else if (i == 0) {
+                       /* Cortex-M0 does not support unaligned memory access */
+                       armv7m->arm.is_armv6m = true;
+               }
+
+               if (i == 4 || i == 3) {
+                       /* Cortex-M3/M4 has 4096 bytes autoincrement range */
+                       armv7m->dap.tar_autoincr_block = (1 << 12);
+               }
+
                /* NOTE: FPB and DWT are both optional. */
 
                /* Setup FPB */
@@ -1848,7 +1940,7 @@ static int cortex_m3_target_request_data(struct target *target,
        uint32_t size, uint8_t *buffer)
 {
        struct armv7m_common *armv7m = target_to_armv7m(target);
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
        uint8_t data;
        uint8_t ctrl;
        uint32_t i;
@@ -1867,7 +1959,7 @@ static int cortex_m3_handle_target_request(void *priv)
        if (!target_was_examined(target))
                return ERROR_OK;
        struct armv7m_common *armv7m = target_to_armv7m(target);
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
 
        if (!target->dbg_msg_enabled)
                return ERROR_OK;
@@ -1918,8 +2010,11 @@ static int cortex_m3_init_arch_info(struct target *target,
        /* Leave (only) generic DAP stuff for debugport_init(); */
        armv7m->dap.jtag_info = &cortex_m3->jtag_info;
        armv7m->dap.memaccess_tck = 8;
-       /* Cortex-M3 has 4096 bytes autoincrement range */
-       armv7m->dap.tar_autoincr_block = (1 << 12);
+
+       /* Cortex-M3/M4 has 4096 bytes autoincrement range
+        * but set a safe default to 1024 to support Cortex-M0
+        * this will be changed in cortex_m3_examine if a M3/M4 is detected */
+       armv7m->dap.tar_autoincr_block = (1 << 10);
 
        /* register arch-specific functions */
        armv7m->examine_debug_reason = cortex_m3_examine_debug_reason;
@@ -1987,7 +2082,7 @@ COMMAND_HANDLER(handle_cortex_m3_vector_catch_command)
        struct target *target = get_current_target(CMD_CTX);
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
        struct armv7m_common *armv7m = &cortex_m3->armv7m;
-       struct adiv5_dap *swjdp = &armv7m->dap;
+       struct adiv5_dap *swjdp = armv7m->arm.dap;
        uint32_t demcr = 0;
        int retval;