target/adi_v5_swd: add support for SWD multidrop
[fw/openocd] / src / target / adi_v5_swd.c
index eb181cb653a0862304c44829bef9a46d763e4b66..c23cee157d53751e0a24f59879f078b76ac83617 100644 (file)
 
 #include <jtag/swd.h>
 
+/* for debug, set do_sync to true to force synchronous transfers */
 static bool do_sync;
 
+static struct adiv5_dap *swd_multidrop_selected_dap;
+
+
+static int swd_queue_dp_write_inner(struct adiv5_dap *dap, unsigned int reg,
+               uint32_t data);
+
+
+static int swd_send_sequence(struct adiv5_dap *dap, enum swd_special_seq seq)
+{
+       const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
+       assert(swd);
+
+       return swd->switch_seq(seq);
+}
+
 static void swd_finish_read(struct adiv5_dap *dap)
 {
        const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
-       if (dap->last_read != NULL) {
+       if (dap->last_read) {
                swd->read_reg(swd_cmd(true, false, DP_RDBUFF), dap->last_read, 0);
                dap->last_read = NULL;
        }
 }
 
-static int swd_queue_dp_write(struct adiv5_dap *dap, unsigned reg,
-               uint32_t data);
-static int swd_queue_dp_read(struct adiv5_dap *dap, unsigned reg,
-               uint32_t *data);
-
 static void swd_clear_sticky_errors(struct adiv5_dap *dap)
 {
        const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
        assert(swd);
 
-       swd->write_reg(swd_cmd(false,  false, DP_ABORT),
+       swd->write_reg(swd_cmd(false, false, DP_ABORT),
                STKCMPCLR | STKERRCLR | WDERRCLR | ORUNERRCLR, 0);
 }
 
@@ -93,17 +104,264 @@ static int swd_run_inner(struct adiv5_dap *dap)
        return retval;
 }
 
-static int swd_connect(struct adiv5_dap *dap)
+static inline int check_sync(struct adiv5_dap *dap)
+{
+       return do_sync ? swd_run_inner(dap) : ERROR_OK;
+}
+
+/** Select the DP register bank matching bits 7:4 of reg. */
+static int swd_queue_dp_bankselect(struct adiv5_dap *dap, unsigned int reg)
 {
+       /* Only register address 4 is banked. */
+       if ((reg & 0xf) != 4)
+               return ERROR_OK;
+
+       uint32_t select_dp_bank = (reg & 0x000000F0) >> 4;
+       uint32_t sel = select_dp_bank
+                       | (dap->select & (DP_SELECT_APSEL | DP_SELECT_APBANK));
+
+       if (sel == dap->select)
+               return ERROR_OK;
+
+       dap->select = sel;
+
+       int retval = swd_queue_dp_write_inner(dap, DP_SELECT, sel);
+       if (retval != ERROR_OK)
+               dap->select = DP_SELECT_INVALID;
+
+       return retval;
+}
+
+static int swd_queue_dp_read_inner(struct adiv5_dap *dap, unsigned int reg,
+               uint32_t *data)
+{
+       const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
+       assert(swd);
+
+       int retval = swd_queue_dp_bankselect(dap, reg);
+       if (retval != ERROR_OK)
+               return retval;
+
+       swd->read_reg(swd_cmd(true, false, reg), data, 0);
+
+       return check_sync(dap);
+}
+
+static int swd_queue_dp_write_inner(struct adiv5_dap *dap, unsigned int reg,
+               uint32_t data)
+{
+       int retval;
        const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
-       uint32_t dpidr;
+       assert(swd);
+
+       swd_finish_read(dap);
+
+       if (reg == DP_SELECT) {
+               dap->select = data & (DP_SELECT_APSEL | DP_SELECT_APBANK | DP_SELECT_DPBANK);
+
+               swd->write_reg(swd_cmd(false, false, reg), data, 0);
+
+               retval = check_sync(dap);
+               if (retval != ERROR_OK)
+                       dap->select = DP_SELECT_INVALID;
+
+               return retval;
+       }
+
+       retval = swd_queue_dp_bankselect(dap, reg);
+       if (retval != ERROR_OK)
+               return retval;
+
+       swd->write_reg(swd_cmd(false, false, reg), data, 0);
+
+       return check_sync(dap);
+}
+
+
+static int swd_multidrop_select_inner(struct adiv5_dap *dap, uint32_t *dpidr_ptr,
+               uint32_t *dlpidr_ptr, bool clear_sticky)
+{
+       int retval;
+       uint32_t dpidr, dlpidr;
+
+       assert(dap_is_multidrop(dap));
+
+       swd_send_sequence(dap, LINE_RESET);
+
+       retval = swd_queue_dp_write_inner(dap, DP_TARGETSEL, dap->multidrop_targetsel);
+       if (retval != ERROR_OK)
+               return retval;
+
+       retval = swd_queue_dp_read_inner(dap, DP_DPIDR, &dpidr);
+       if (retval != ERROR_OK)
+               return retval;
+
+       if (clear_sticky) {
+               /* Clear all sticky errors (including ORUN) */
+               swd_clear_sticky_errors(dap);
+       } else {
+               /* Ideally just clear ORUN flag which is set by reset */
+               retval = swd_queue_dp_write_inner(dap, DP_ABORT, ORUNERRCLR);
+               if (retval != ERROR_OK)
+                       return retval;
+       }
+
+       retval = swd_queue_dp_read_inner(dap, DP_DLPIDR, &dlpidr);
+       if (retval != ERROR_OK)
+               return retval;
+
+       retval = swd_run_inner(dap);
+       if (retval != ERROR_OK)
+               return retval;
+
+       if ((dpidr & DP_DPIDR_VERSION_MASK) < (2UL << DP_DPIDR_VERSION_SHIFT)) {
+               LOG_INFO("Read DPIDR 0x%08" PRIx32
+                                " has version < 2. A non multidrop capable device connected?",
+                                dpidr);
+               return ERROR_FAIL;
+       }
+
+       /* TODO: check TARGETID if DLIPDR is same for more than one DP */
+       uint32_t expected_dlpidr = DP_DLPIDR_PROTVSN |
+                       (dap->multidrop_targetsel & DP_TARGETSEL_INSTANCEID_MASK);
+       if (dlpidr != expected_dlpidr) {
+               LOG_INFO("Read incorrect DLPIDR 0x%08" PRIx32
+                                " (possibly CTRL/STAT value)",
+                                dlpidr);
+               return ERROR_FAIL;
+       }
+
+       LOG_DEBUG_IO("Selected DP_TARGETSEL 0x%08" PRIx32, dap->multidrop_targetsel);
+       swd_multidrop_selected_dap = dap;
+
+       if (dpidr_ptr)
+               *dpidr_ptr = dpidr;
+
+       if (dlpidr_ptr)
+               *dlpidr_ptr = dlpidr;
+
+       return retval;
+}
+
+static int swd_multidrop_select(struct adiv5_dap *dap)
+{
+       if (!dap_is_multidrop(dap))
+               return ERROR_OK;
+
+       if (swd_multidrop_selected_dap == dap)
+               return ERROR_OK;
+
+       int retval = ERROR_OK;
+       for (unsigned int retry = 0; ; retry++) {
+               bool clear_sticky = retry > 0;
+
+               retval = swd_multidrop_select_inner(dap, NULL, NULL, clear_sticky);
+               if (retval == ERROR_OK)
+                       break;
+
+               swd_multidrop_selected_dap = NULL;
+               if (retry > 3) {
+                       LOG_ERROR("Failed to select multidrop %s", adiv5_dap_name(dap));
+                       return retval;
+               }
+
+               LOG_DEBUG("Failed to select multidrop %s, retrying...",
+                                 adiv5_dap_name(dap));
+       }
+
+       return retval;
+}
+
+static int swd_connect_multidrop(struct adiv5_dap *dap)
+{
+       int retval;
+       uint32_t dpidr = 0xdeadbeef;
+       uint32_t dlpidr = 0xdeadbeef;
+       int64_t timeout = timeval_ms() + 500;
+
+       do {
+               swd_send_sequence(dap, JTAG_TO_DORMANT);
+               swd_send_sequence(dap, DORMANT_TO_SWD);
+
+               /* Clear link state, including the SELECT cache. */
+               dap->do_reconnect = false;
+               dap_invalidate_cache(dap);
+               swd_multidrop_selected_dap = NULL;
+
+               retval = swd_multidrop_select_inner(dap, &dpidr, &dlpidr, true);
+               if (retval == ERROR_OK)
+                       break;
+
+               alive_sleep(1);
+
+       } while (timeval_ms() < timeout);
+
+       if (retval != ERROR_OK) {
+               swd_multidrop_selected_dap = NULL;
+               LOG_ERROR("Failed to connect multidrop %s", adiv5_dap_name(dap));
+               return retval;
+       }
+
+       LOG_INFO("SWD DPIDR 0x%08" PRIx32 ", DLPIDR 0x%08" PRIx32,
+                         dpidr, dlpidr);
+
+       return retval;
+}
+
+static int swd_connect_single(struct adiv5_dap *dap)
+{
+       int retval;
+       uint32_t dpidr = 0xdeadbeef;
+       int64_t timeout = timeval_ms() + 500;
+
+       do {
+               swd_send_sequence(dap, JTAG_TO_SWD);
+
+               /* Clear link state, including the SELECT cache. */
+               dap->do_reconnect = false;
+               dap_invalidate_cache(dap);
+
+               retval = swd_queue_dp_read_inner(dap, DP_DPIDR, &dpidr);
+               if (retval == ERROR_OK) {
+                       retval = swd_run_inner(dap);
+                       if (retval == ERROR_OK)
+                               break;
+               }
+
+               alive_sleep(1);
+
+       } while (timeval_ms() < timeout);
+
+       if (retval != ERROR_OK) {
+               LOG_ERROR("Error connecting DP: cannot read IDR");
+               return retval;
+       }
+
+       LOG_INFO("SWD DPIDR 0x%08" PRIx32, dpidr);
+
+       do {
+               dap->do_reconnect = false;
+
+               /* force clear all sticky faults */
+               swd_clear_sticky_errors(dap);
+
+               retval = swd_run_inner(dap);
+               if (retval != ERROR_WAIT)
+                       break;
+
+               alive_sleep(10);
+
+       } while (timeval_ms() < timeout);
+
+       return retval;
+}
+
+static int swd_connect(struct adiv5_dap *dap)
+{
        int status;
 
        /* FIXME validate transport config ... is the
         * configured DAP present (check IDCODE)?
-        * Is *only* one DAP configured?
-        *
-        * MUST READ DPIDR
         */
 
        /* Check if we should reset srst already when connecting, but not if reconnecting. */
@@ -112,41 +370,43 @@ static int swd_connect(struct adiv5_dap *dap)
 
                if (jtag_reset_config & RESET_CNCT_UNDER_SRST) {
                        if (jtag_reset_config & RESET_SRST_NO_GATING)
-                               swd_add_reset(1);
+                               adapter_assert_reset();
                        else
                                LOG_WARNING("\'srst_nogate\' reset_config option is required");
                }
        }
 
-       /* Note, debugport_init() does setup too */
-       swd->switch_seq(JTAG_TO_SWD);
+       if (dap_is_multidrop(dap))
+               status = swd_connect_multidrop(dap);
+       else
+               status = swd_connect_single(dap);
 
-       /* Clear link state, including the SELECT cache. */
-       dap->do_reconnect = false;
-       dap_invalidate_cache(dap);
+       /* IHI 0031E B4.3.2:
+        * "A WAIT response must not be issued to the ...
+        * ... writes to the ABORT register"
+        * swd_clear_sticky_errors() writes to the ABORT register only.
+        *
+        * Unfortunately at least Microchip SAMD51/E53/E54 returns WAIT
+        * in a corner case. Just try if ABORT resolves the problem.
+        */
+       if (status == ERROR_WAIT) {
+               LOG_WARNING("Connecting DP: stalled AP operation, issuing ABORT");
 
-       swd_queue_dp_read(dap, DP_DPIDR, &dpidr);
+               dap->do_reconnect = false;
 
-       /* force clear all sticky faults */
-       swd_clear_sticky_errors(dap);
+               status = swd_queue_dp_write_inner(dap, DP_ABORT,
+                       DAPABORT | STKCMPCLR | STKERRCLR | WDERRCLR | ORUNERRCLR);
 
-       status = swd_run_inner(dap);
+               if (status == ERROR_OK)
+                       status = swd_run_inner(dap);
+       }
 
-       if (status == ERROR_OK) {
-               LOG_INFO("SWD DPIDR %#8.8" PRIx32, dpidr);
-               dap->do_reconnect = false;
+       if (status == ERROR_OK)
                status = dap_dp_init(dap);
-       } else
-               dap->do_reconnect = true;
 
        return status;
 }
 
-static inline int check_sync(struct adiv5_dap *dap)
-{
-       return do_sync ? swd_run_inner(dap) : ERROR_OK;
-}
-
 static int swd_check_reconnect(struct adiv5_dap *dap)
 {
        if (dap->do_reconnect)
@@ -160,44 +420,31 @@ static int swd_queue_ap_abort(struct adiv5_dap *dap, uint8_t *ack)
        const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
        assert(swd);
 
-       swd->write_reg(swd_cmd(false,  false, DP_ABORT),
+       /* TODO: Send DAPABORT in swd_multidrop_select_inner()
+        * in the case the multidrop dap is not selected?
+        * swd_queue_ap_abort() is not currently used anyway...
+        */
+       int retval = swd_multidrop_select(dap);
+       if (retval != ERROR_OK)
+               return retval;
+
+       swd->write_reg(swd_cmd(false, false, DP_ABORT),
                DAPABORT | STKCMPCLR | STKERRCLR | WDERRCLR | ORUNERRCLR, 0);
        return check_sync(dap);
 }
 
-/** Select the DP register bank matching bits 7:4 of reg. */
-static void swd_queue_dp_bankselect(struct adiv5_dap *dap, unsigned reg)
-{
-       /* Only register address 4 is banked. */
-       if ((reg & 0xf) != 4)
-               return;
-
-       uint32_t select_dp_bank = (reg & 0x000000F0) >> 4;
-       uint32_t sel = select_dp_bank
-                       | (dap->select & (DP_SELECT_APSEL | DP_SELECT_APBANK));
-
-       if (sel == dap->select)
-               return;
-
-       dap->select = sel;
-
-       swd_queue_dp_write(dap, DP_SELECT, sel);
-}
-
 static int swd_queue_dp_read(struct adiv5_dap *dap, unsigned reg,
                uint32_t *data)
 {
-       const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
-       assert(swd);
-
        int retval = swd_check_reconnect(dap);
        if (retval != ERROR_OK)
                return retval;
 
-       swd_queue_dp_bankselect(dap, reg);
-       swd->read_reg(swd_cmd(true,  false, reg), data, 0);
+       retval = swd_multidrop_select(dap);
+       if (retval != ERROR_OK)
+               return retval;
 
-       return check_sync(dap);
+       return swd_queue_dp_read_inner(dap, reg, data);
 }
 
 static int swd_queue_dp_write(struct adiv5_dap *dap, unsigned reg,
@@ -210,15 +457,15 @@ static int swd_queue_dp_write(struct adiv5_dap *dap, unsigned reg,
        if (retval != ERROR_OK)
                return retval;
 
-       swd_finish_read(dap);
-       swd_queue_dp_bankselect(dap, reg);
-       swd->write_reg(swd_cmd(false,  false, reg), data, 0);
+       retval = swd_multidrop_select(dap);
+       if (retval != ERROR_OK)
+               return retval;
 
-       return check_sync(dap);
+       return swd_queue_dp_write_inner(dap, reg, data);
 }
 
 /** Select the AP register bank matching bits 7:4 of reg. */
-static void swd_queue_ap_bankselect(struct adiv5_ap *ap, unsigned reg)
+static int swd_queue_ap_bankselect(struct adiv5_ap *ap, unsigned reg)
 {
        struct adiv5_dap *dap = ap->dap;
        uint32_t sel = ((uint32_t)ap->ap_num << 24)
@@ -226,11 +473,15 @@ static void swd_queue_ap_bankselect(struct adiv5_ap *ap, unsigned reg)
                        | (dap->select & DP_SELECT_DPBANK);
 
        if (sel == dap->select)
-               return;
+               return ERROR_OK;
 
        dap->select = sel;
 
-       swd_queue_dp_write(dap, DP_SELECT, sel);
+       int retval = swd_queue_dp_write_inner(dap, DP_SELECT, sel);
+       if (retval != ERROR_OK)
+               dap->select = DP_SELECT_INVALID;
+
+       return retval;
 }
 
 static int swd_queue_ap_read(struct adiv5_ap *ap, unsigned reg,
@@ -244,8 +495,15 @@ static int swd_queue_ap_read(struct adiv5_ap *ap, unsigned reg,
        if (retval != ERROR_OK)
                return retval;
 
-       swd_queue_ap_bankselect(ap, reg);
-       swd->read_reg(swd_cmd(true,  true, reg), dap->last_read, ap->memaccess_tck);
+       retval = swd_multidrop_select(dap);
+       if (retval != ERROR_OK)
+               return retval;
+
+       retval = swd_queue_ap_bankselect(ap, reg);
+       if (retval != ERROR_OK)
+               return retval;
+
+       swd->read_reg(swd_cmd(true, true, reg), dap->last_read, ap->memaccess_tck);
        dap->last_read = data;
 
        return check_sync(dap);
@@ -262,9 +520,17 @@ static int swd_queue_ap_write(struct adiv5_ap *ap, unsigned reg,
        if (retval != ERROR_OK)
                return retval;
 
+       retval = swd_multidrop_select(dap);
+       if (retval != ERROR_OK)
+               return retval;
+
        swd_finish_read(dap);
-       swd_queue_ap_bankselect(ap, reg);
-       swd->write_reg(swd_cmd(false,  true, reg), data, ap->memaccess_tck);
+
+       retval = swd_queue_ap_bankselect(ap, reg);
+       if (retval != ERROR_OK)
+               return retval;
+
+       swd->write_reg(swd_cmd(false, true, reg), data, ap->memaccess_tck);
 
        return check_sync(dap);
 }
@@ -272,7 +538,12 @@ static int swd_queue_ap_write(struct adiv5_ap *ap, unsigned reg,
 /** Executes all queued DAP operations. */
 static int swd_run(struct adiv5_dap *dap)
 {
+       int retval = swd_multidrop_select(dap);
+       if (retval != ERROR_OK)
+               return retval;
+
        swd_finish_read(dap);
+
        return swd_run_inner(dap);
 }
 
@@ -280,14 +551,33 @@ static int swd_run(struct adiv5_dap *dap)
 static void swd_quit(struct adiv5_dap *dap)
 {
        const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
+       static bool done;
+
+       /* There is no difference if the sequence is sent at the last
+        * or the first swd_quit() call, send it just once */
+       if (done)
+               return;
+
+       done = true;
+       if (dap_is_multidrop(dap)) {
+               swd->switch_seq(SWD_TO_DORMANT);
+               /* Revisit!
+                * Leaving DPs in dormant state was tested and offers some safety
+                * against DPs mismatch in case of unintentional use of non-multidrop SWD.
+                * To put SWJ-DPs to power-on state issue
+                * swd->switch_seq(DORMANT_TO_JTAG);
+                */
+       } else {
+               swd->switch_seq(SWD_TO_JTAG);
+       }
 
-       swd->switch_seq(SWD_TO_JTAG);
-       /* flush the queue before exit */
+       /* flush the queue to shift out the sequence before exit */
        swd->run();
 }
 
 const struct dap_ops swd_dap_ops = {
        .connect = swd_connect,
+       .send_sequence = swd_send_sequence,
        .queue_dp_read = swd_queue_dp_read,
        .queue_dp_write = swd_queue_dp_write,
        .queue_ap_read = swd_queue_ap_read,
@@ -320,15 +610,16 @@ static const struct command_registration swd_handlers[] = {
                .mode = COMMAND_ANY,
                .help = "SWD command group",
                .chain = swd_commands,
+               .usage = "",
        },
        COMMAND_REGISTRATION_DONE
 };
 
 static int swd_select(struct command_context *ctx)
 {
-       /* FIXME: only place where global 'jtag_interface' is still needed */
-       extern struct jtag_interface *jtag_interface;
-       const struct swd_driver *swd = jtag_interface->swd;
+       /* FIXME: only place where global 'adapter_driver' is still needed */
+       extern struct adapter_driver *adapter_driver;
+       const struct swd_driver *swd = adapter_driver->swd_ops;
        int retval;
 
        retval = register_commands(ctx, NULL, swd_handlers);