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authorJulius Werner <jwerner@chromium.org>2019-06-05 12:40:35 -0700
committerJulius Werner <jwerner@chromium.org>2020-08-24 18:38:47 -0700
commitf40008a4be26dc43cbf50f68c4f20803ea735807 (patch)
tree5f511e26f6660bb963abad6c6a99af51972d753c /plat/qti
parent2acf00433023a16ff5f076e2d551961567c022d5 (diff)
downloadtrusted-firmware-a-f40008a4be26dc43cbf50f68c4f20803ea735807.tar.gz
qti: Add SPMI PMIC arbitrator driver
This patch adds a very rudimentary driver for the SPMI arbitrator used to access the PMIC. It doesn't support all the controller's actual arbitration features, so it should probably not be used concurrently with a running kernel (and it's also not optimized for performance). But it can be used to set a few registers during boot or on shutdown to control reset handling, which is all we need it for. Change-Id: I8631c34a2a89ac71aa1ec9b8266e818c922fe34a Signed-off-by: Julius Werner <jwerner@chromium.org>
Diffstat (limited to 'plat/qti')
-rw-r--r--plat/qti/common/inc/spmi_arb.h23
-rw-r--r--plat/qti/common/src/spmi_arb.c113
2 files changed, 136 insertions, 0 deletions
diff --git a/plat/qti/common/inc/spmi_arb.h b/plat/qti/common/inc/spmi_arb.h
new file mode 100644
index 0000000000..362f7406cf
--- /dev/null
+++ b/plat/qti/common/inc/spmi_arb.h
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2020, Google LLC. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef SPMI_ARB_H
+#define SPMI_ARB_H
+
+#include <stdint.h>
+
+/*******************************************************************************
+ * WARNING: This driver does not arbitrate access with the kernel. These APIs
+ * must only be called when the kernel is known to be quiesced (such as before
+ * boot or while the system is shutting down).
+ ******************************************************************************/
+
+/* 32-bit addresses combine (U)SID, PID and register address. */
+
+int spmi_arb_read8(uint32_t addr);
+int spmi_arb_write8(uint32_t addr, uint8_t data);
+
+#endif /* SPMI_ARB_H */
diff --git a/plat/qti/common/src/spmi_arb.c b/plat/qti/common/src/spmi_arb.c
new file mode 100644
index 0000000000..81cc577293
--- /dev/null
+++ b/plat/qti/common/src/spmi_arb.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2020, Google LLC. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <common/debug.h>
+#include <drivers/delay_timer.h>
+#include <lib/mmio.h>
+
+#include <spmi_arb.h>
+
+#define REG_APID_MAP(apid) (0x0C440900 + 4 * i)
+#define NUM_APID 0x80
+
+#define PPID_MASK (0xfff << 8)
+
+#define REG_ARB_CMD(apid) (0x0C600000 + 0x10000 * apid)
+/* These are opcodes specific to this SPMI arbitrator, *not* SPMI commands. */
+#define OPC_EXT_WRITEL 0
+#define OPC_EXT_READL 1
+
+#define REG_ARB_STATUS(apid) (0x0C600008 + 0x10000 * apid)
+#define ARB_STATUS_DONE BIT(0)
+#define ARB_STATUS_FAILURE BIT(1)
+#define ARB_STATUS_DENIED BIT(2)
+#define ARB_STATUS_DROPPED BIT(3)
+
+/* Fake status to report driver errors. */
+#define ARB_FAKE_STATUS_TIMEOUT BIT(8)
+
+#define REG_ARB_RDATA0(apid) (0x0C600018 + 0x10000 * apid)
+#define REG_ARB_WDATA0(apid) (0x0C600010 + 0x10000 * apid)
+
+static int addr_to_apid(uint32_t addr)
+{
+ unsigned int i;
+
+ for (i = 0U; i < NUM_APID; i++) {
+ uint32_t reg = mmio_read_32(REG_APID_MAP(i));
+ if ((reg != 0U) && ((addr & PPID_MASK) == (reg & PPID_MASK))) {
+ return i;
+ }
+ }
+
+ return -1;
+}
+
+static int wait_for_done(uint16_t apid)
+{
+ unsigned int timeout = 100;
+
+ while (timeout-- != 0U) {
+ uint32_t status = mmio_read_32(REG_ARB_STATUS(apid));
+ if ((status & ARB_STATUS_DONE) != 0U) {
+ if ((status & ARB_STATUS_FAILURE) != 0U ||
+ (status & ARB_STATUS_DENIED) != 0U ||
+ (status & ARB_STATUS_DROPPED) != 0U) {
+ return status & 0xff;
+ }
+ return 0;
+ }
+ mdelay(1);
+ }
+ ERROR("SPMI_ARB timeout!\n");
+ return ARB_FAKE_STATUS_TIMEOUT;
+}
+
+static void arb_command(uint16_t apid, uint8_t opcode, uint32_t addr,
+ uint8_t bytes)
+{
+ mmio_write_32(REG_ARB_CMD(apid), (uint32_t)opcode << 27 |
+ (addr & 0xff) << 4 | (bytes - 1));
+}
+
+int spmi_arb_read8(uint32_t addr)
+{
+ int apid = addr_to_apid(addr);
+
+ if (apid < 0) {
+ return apid;
+ }
+
+ arb_command(apid, OPC_EXT_READL, addr, 1);
+
+ int ret = wait_for_done(apid);
+ if (ret != 0) {
+ ERROR("SPMI_ARB read error [0x%x]: 0x%x\n", addr, ret);
+ return ret;
+ }
+
+ return mmio_read_32(REG_ARB_RDATA0(apid)) & 0xff;
+}
+
+int spmi_arb_write8(uint32_t addr, uint8_t data)
+{
+ int apid = addr_to_apid(addr);
+
+ if (apid < 0) {
+ return apid;
+ }
+
+ mmio_write_32(REG_ARB_WDATA0(apid), data);
+ arb_command(apid, OPC_EXT_WRITEL, addr, 1);
+
+ int ret = wait_for_done(apid);
+ if (ret != 0) {
+ ERROR("SPMI_ARB write error [0x%x] = 0x%x: 0x%x\n",
+ addr, data, ret);
+ }
+
+ return ret;
+}