mpc83xx: Add sysreset driver
Add a sysreset driver for the MPC83xx platform.
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/drivers/sysreset/sysreset_mpc83xx.c b/drivers/sysreset/sysreset_mpc83xx.c
new file mode 100644
index 0000000..9092764
--- /dev/null
+++ b/drivers/sysreset/sysreset_mpc83xx.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2018
+ * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <sysreset.h>
+#include <wait_bit.h>
+
+#include "sysreset_mpc83xx.h"
+
+/* Magic 4-byte word to enable reset ('RSTE' in ASCII) */
+static const u32 RPR_MAGIC = 0x52535445;
+/* Wait at most 2000ms for reset control enable bit */
+static const uint RESET_WAIT_TIMEOUT = 2000;
+
+/**
+ * __do_reset() - Execute the system reset
+ *
+ * Return: The functions resets the system, and never returns.
+ */
+static int __do_reset(void)
+{
+ ulong msr;
+ int res;
+
+ immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
+
+ puts("Resetting the board.\n");
+
+ /* Interrupts and MMU off */
+ msr = mfmsr();
+ msr &= ~(MSR_EE | MSR_IR | MSR_DR);
+ mtmsr(msr);
+
+ /* Enable Reset Control Reg */
+ out_be32(&immap->reset.rpr, RPR_MAGIC);
+ sync();
+ isync();
+
+ /* Confirm Reset Control Reg is enabled */
+ res = wait_for_bit_be32(&immap->reset.rcer, RCER_CRE, true,
+ RESET_WAIT_TIMEOUT, false);
+ if (res) {
+ debug("%s: Timed out waiting for reset control to be set\n",
+ __func__);
+ return res;
+ }
+
+ udelay(200);
+
+ /* Perform reset, only one bit */
+ out_be32(&immap->reset.rcr, RCR_SWHR);
+
+ /* Never executes */
+ return 0;
+}
+
+static int mpc83xx_sysreset_request(struct udevice *dev, enum sysreset_t type)
+{
+ switch (type) {
+ case SYSRESET_WARM:
+ case SYSRESET_COLD:
+ return __do_reset();
+ default:
+ return -EPROTONOSUPPORT;
+ }
+
+ return -EINPROGRESS;
+}
+
+/**
+ * print_83xx_arb_event() - Print arbiter events to buffer
+ * @force: Print arbiter events, even if none are indicated by the system
+ * @buf: The buffer to receive the printed arbiter event information
+ * @size: The size of the buffer to receive the printed arbiter event
+ * information in bytes
+ *
+ * Return: Number of bytes printed to buffer, -ve on error
+ */
+static int print_83xx_arb_event(bool force, char *buf, int size)
+{
+ int etype = (gd->arch.arbiter_event_attributes & AEATR_EVENT)
+ >> AEATR_EVENT_SHIFT;
+ int mstr_id = (gd->arch.arbiter_event_attributes & AEATR_MSTR_ID)
+ >> AEATR_MSTR_ID_SHIFT;
+ int tbst = (gd->arch.arbiter_event_attributes & AEATR_TBST)
+ >> AEATR_TBST_SHIFT;
+ int tsize = (gd->arch.arbiter_event_attributes & AEATR_TSIZE)
+ >> AEATR_TSIZE_SHIFT;
+ int ttype = (gd->arch.arbiter_event_attributes & AEATR_TTYPE)
+ >> AEATR_TTYPE_SHIFT;
+ int tsize_val = (tbst << 3) | tsize;
+ int tsize_bytes = tbst ? (tsize ? tsize : 8) : 16 + 8 * tsize;
+ int res = 0;
+
+ /*
+ * If we don't force output, and there is no event (event address ==
+ * 0), then don't print anything
+ */
+ if (!force && !gd->arch.arbiter_event_address)
+ return 0;
+
+ if (CONFIG_IS_ENABLED(CONFIG_DISPLAY_AER_FULL)) {
+ res = snprintf(buf, size,
+ "Arbiter Event Status:\n"
+ " %s: 0x%08lX\n"
+ " %s: 0x%1x = %s\n"
+ " %s: 0x%02x = %s\n"
+ " %s: 0x%1x = %d bytes\n"
+ " %s: 0x%02x = %s\n",
+ "Event Address", gd->arch.arbiter_event_address,
+ "Event Type", etype, event[etype],
+ "Master ID", mstr_id, master[mstr_id],
+ "Transfer Size", tsize_val, tsize_bytes,
+ "Transfer Type", ttype, transfer[ttype]);
+ } else if (CONFIG_IS_ENABLED(CONFIG_DISPLAY_AER_BRIEF)) {
+ res = snprintf(buf, size,
+ "Arbiter Event Status: AEATR=0x%08lX, AEADR=0x%08lX\n",
+ gd->arch.arbiter_event_attributes,
+ gd->arch.arbiter_event_address);
+ }
+
+ return res;
+}
+
+static int mpc83xx_sysreset_get_status(struct udevice *dev, char *buf, int size)
+{
+ /* Ad-hoc data structure to map RSR bit values to their descriptions */
+ static const struct {
+ /* Bit mask for the bit in question */
+ ulong mask;
+ /* Description of the bitmask in question */
+ char *desc;
+ } bits[] = {
+ {
+ RSR_SWSR, "Software Soft"}, {
+ RSR_SWHR, "Software Hard"}, {
+ RSR_JSRS, "JTAG Soft"}, {
+ RSR_CSHR, "Check Stop"}, {
+ RSR_SWRS, "Software Watchdog"}, {
+ RSR_BMRS, "Bus Monitor"}, {
+ RSR_SRS, "External/Internal Soft"}, {
+ RSR_HRS, "External/Internal Hard"}
+ };
+ int res;
+ ulong rsr = gd->arch.reset_status;
+ int i;
+ char *sep;
+
+ res = snprintf(buf, size, "Reset Status:");
+ if (res < 0) {
+ debug("%s: Could not write reset status message (err = %d)\n",
+ dev->name, res);
+ return -EIO;
+ }
+
+ buf += res;
+ size -= res;
+
+ sep = " ";
+ for (i = 0; i < ARRAY_SIZE(bits); i++)
+ /* Print description of set bits */
+ if (rsr & bits[i].mask) {
+ res = snprintf(buf, size, "%s%s%s", sep, bits[i].desc,
+ (i == ARRAY_SIZE(bits) - 1) ? "\n" : "");
+ if (res < 0) {
+ debug("%s: Could not write reset status message (err = %d)\n",
+ dev->name, res);
+ return -EIO;
+ }
+ buf += res;
+ size -= res;
+ sep = ", ";
+ }
+
+ /*
+ * TODO(mario.six@gdsys.cc): Move this into a dedicated
+ * arbiter driver
+ */
+ if (CONFIG_IS_ENABLED(CONFIG_DISPLAY_AER_FULL) ||
+ CONFIG_IS_ENABLED(CONFIG_DISPLAY_AER_BRIEF)) {
+ /*
+ * If there was a bus monitor reset event, we force the arbiter
+ * event to be printed
+ */
+ res = print_83xx_arb_event(rsr & RSR_BMRS, buf, size);
+ if (res < 0) {
+ debug("%s: Could not write arbiter event message (err = %d)\n",
+ dev->name, res);
+ return -EIO;
+ }
+ buf += res;
+ size -= res;
+ }
+ snprintf(buf, size, "\n");
+
+ return 0;
+}
+
+static struct sysreset_ops mpc83xx_sysreset = {
+ .request = mpc83xx_sysreset_request,
+ .get_status = mpc83xx_sysreset_get_status,
+};
+
+U_BOOT_DRIVER(sysreset_mpc83xx) = {
+ .name = "mpc83xx_sysreset",
+ .id = UCLASS_SYSRESET,
+ .ops = &mpc83xx_sysreset,
+};
