Merge tag 'qcom-drivers-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux into arm/drivers

Qualcomm driver updates for v5.8

This contains a large set of cleanups, bug fixes, general improvements
and documentation fixes for the RPMH driver. It adds a debugfs mechanism
for inspecting Command DB. Socinfo got the "soc_id" attribute defines
and definitions for a various variants of MSM8939.

RPMH, RPMPD and RPMHPD where made possible to build as modules, but RPMH
had to be reverted due to a compilation issue when tracing is enabled.

RPMHPD gained power-domains for the SM8250 voltage corners.

The SCM driver gained fixes for two build warnings and the SMP2P had an
unnecessary error print removed.

* tag 'qcom-drivers-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux: (42 commits)
  Revert "soc: qcom: rpmh: Allow RPMH driver to be loaded as a module"
  soc: qcom: rpmh-rsc: Remove the pm_lock
  soc: qcom: rpmh-rsc: Simplify locking by eliminating the per-TCS lock
  kernel/cpu_pm: Fix uninitted local in cpu_pm
  soc: qcom: rpmh-rsc: We aren't notified of our own failure w/ NOTIFY_BAD
  soc: qcom: rpmh-rsc: Correctly ignore CPU_CLUSTER_PM notifications
  firmware: qcom_scm-legacy: Replace zero-length array with flexible-array
  soc: qcom: rpmh-rsc: Timeout after 1 second in write_tcs_reg_sync()
  soc: qcom: rpmh-rsc: Factor "tcs_reg_addr" and "tcs_cmd_addr" calculation
  soc: qcom: socinfo: add msm8936/39 and apq8036/39 soc ids
  soc: qcom: aoss: Add SM8250 compatible
  soc: qcom: pdr: Remove impossible error condition
  soc: qcom: rpmh: Dirt can only make you dirtier, not cleaner
  soc: qcom: rpmhpd: Add SM8250 power domains
  firmware: qcom_scm: fix bogous abuse of dma-direct internals
  dt-bindings: soc: qcom: apr: Use generic node names for APR services
  firmware: qcom_scm: Remove unneeded conversion to bool
  soc: qcom: cmd-db: Properly endian swap the slv_id for debugfs
  soc: qcom: cmd-db: Use 5 digits for printing address
  soc: qcom: cmd-db: Cast sizeof() to int to silence field width warning
  ...

Link: https://lore.kernel.org/r/20200519052533.1250024-1-bjorn.andersson@linaro.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

11 files changed, 743 insertions, 287 deletions

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index bf42a17a45de..19332ea40234 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -117,7 +117,7 @@ config QCOM_RPMH
 	  help apply the aggregated state on the resource.
 
 config QCOM_RPMHPD
-	bool "Qualcomm RPMh Power domain driver"
+	tristate "Qualcomm RPMh Power domain driver"
 	depends on QCOM_RPMH && QCOM_COMMAND_DB
 	help
 	  QCOM RPMh Power domain driver to support power-domains with
@@ -126,8 +126,8 @@ config QCOM_RPMHPD
 	  for the voltage rail.
 
 config QCOM_RPMPD
-	bool "Qualcomm RPM Power domain driver"
-	depends on QCOM_SMD_RPM=y
+	tristate "Qualcomm RPM Power domain driver"
+	depends on QCOM_SMD_RPM
 	help
 	  QCOM RPM Power domain driver to support power-domains with
 	  performance states. The driver communicates a performance state
diff --git a/drivers/soc/qcom/cmd-db.c b/drivers/soc/qcom/cmd-db.c
index f6c3d17b05c7..fc5610603b17 100644
--- a/drivers/soc/qcom/cmd-db.c
+++ b/drivers/soc/qcom/cmd-db.c
@@ -1,12 +1,13 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /* Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. */
 
+#include <linux/debugfs.h>
 #include <linux/kernel.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
-#include <linux/of_platform.h>
 #include <linux/of_reserved_mem.h>
 #include <linux/platform_device.h>
+#include <linux/seq_file.h>
 #include <linux/types.h>
 
 #include <soc/qcom/cmd-db.h>
@@ -236,6 +237,77 @@ enum cmd_db_hw_type cmd_db_read_slave_id(const char *id)
 }
 EXPORT_SYMBOL(cmd_db_read_slave_id);
 
+#ifdef CONFIG_DEBUG_FS
+static int cmd_db_debugfs_dump(struct seq_file *seq, void *p)
+{
+	int i, j;
+	const struct rsc_hdr *rsc;
+	const struct entry_header *ent;
+	const char *name;
+	u16 len, version;
+	u8 major, minor;
+
+	seq_puts(seq, "Command DB DUMP\n");
+
+	for (i = 0; i < MAX_SLV_ID; i++) {
+		rsc = &cmd_db_header->header[i];
+		if (!rsc->slv_id)
+			break;
+
+		switch (le16_to_cpu(rsc->slv_id)) {
+		case CMD_DB_HW_ARC:
+			name = "ARC";
+			break;
+		case CMD_DB_HW_VRM:
+			name = "VRM";
+			break;
+		case CMD_DB_HW_BCM:
+			name = "BCM";
+			break;
+		default:
+			name = "Unknown";
+			break;
+		}
+
+		version = le16_to_cpu(rsc->version);
+		major = version >> 8;
+		minor = version;
+
+		seq_printf(seq, "Slave %s (v%u.%u)\n", name, major, minor);
+		seq_puts(seq, "-------------------------\n");
+
+		ent = rsc_to_entry_header(rsc);
+		for (j = 0; j < le16_to_cpu(rsc->cnt); j++, ent++) {
+			seq_printf(seq, "0x%05x: %*pEp", le32_to_cpu(ent->addr),
+				   (int)sizeof(ent->id), ent->id);
+
+			len = le16_to_cpu(ent->len);
+			if (len) {
+				seq_printf(seq, " [%*ph]",
+					   len, rsc_offset(rsc, ent));
+			}
+			seq_putc(seq, '\n');
+		}
+	}
+
+	return 0;
+}
+
+static int open_cmd_db_debugfs(struct inode *inode, struct file *file)
+{
+	return single_open(file, cmd_db_debugfs_dump, inode->i_private);
+}
+#endif
+
+static const struct file_operations cmd_db_debugfs_ops = {
+#ifdef CONFIG_DEBUG_FS
+	.open = open_cmd_db_debugfs,
+#endif
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
 static int cmd_db_dev_probe(struct platform_device *pdev)
 {
 	struct reserved_mem *rmem;
@@ -259,12 +331,14 @@ static int cmd_db_dev_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
+	debugfs_create_file("cmd-db", 0400, NULL, NULL, &cmd_db_debugfs_ops);
+
 	return 0;
 }
 
 static const struct of_device_id cmd_db_match_table[] = {
 	{ .compatible = "qcom,cmd-db" },
-	{ },
+	{ }
 };
 
 static struct platform_driver cmd_db_dev_driver = {
diff --git a/drivers/soc/qcom/pdr_interface.c b/drivers/soc/qcom/pdr_interface.c
index 17ad3b8698e1..bdcf16f88a97 100644
--- a/drivers/soc/qcom/pdr_interface.c
+++ b/drivers/soc/qcom/pdr_interface.c
@@ -155,10 +155,6 @@ static int pdr_register_listener(struct pdr_handle *pdr,
 		return ret;
 	}
 
-	if ((int)resp.curr_state < INT_MIN || (int)resp.curr_state > INT_MAX)
-		pr_err("PDR: %s notification state invalid: 0x%x\n",
-		       pds->service_path, resp.curr_state);
-
 	pds->state = resp.curr_state;
 
 	return 0;
diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
index f43a2e07ee83..ed2c687c16b3 100644
--- a/drivers/soc/qcom/qcom_aoss.c
+++ b/drivers/soc/qcom/qcom_aoss.c
@@ -599,6 +599,7 @@ static const struct of_device_id qmp_dt_match[] = {
 	{ .compatible = "qcom,sc7180-aoss-qmp", },
 	{ .compatible = "qcom,sdm845-aoss-qmp", },
 	{ .compatible = "qcom,sm8150-aoss-qmp", },
+	{ .compatible = "qcom,sm8250-aoss-qmp", },
 	{}
 };
 MODULE_DEVICE_TABLE(of, qmp_dt_match);
diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h
index 6eec32b97f83..ef60e790a750 100644
--- a/drivers/soc/qcom/rpmh-internal.h
+++ b/drivers/soc/qcom/rpmh-internal.h
@@ -22,16 +22,23 @@ struct rsc_drv;
  * struct tcs_group: group of Trigger Command Sets (TCS) to send state requests
  * to the controller
  *
- * @drv:       the controller
- * @type:      type of the TCS in this group - active, sleep, wake
- * @mask:      mask of the TCSes relative to all the TCSes in the RSC
- * @offset:    start of the TCS group relative to the TCSes in the RSC
- * @num_tcs:   number of TCSes in this type
- * @ncpt:      number of commands in each TCS
- * @lock:      lock for synchronizing this TCS writes
- * @req:       requests that are sent from the TCS
- * @cmd_cache: flattened cache of cmds in sleep/wake TCS
- * @slots:     indicates which of @cmd_addr are occupied
+ * @drv:       The controller.
+ * @type:      Type of the TCS in this group - active, sleep, wake.
+ * @mask:      Mask of the TCSes relative to all the TCSes in the RSC.
+ * @offset:    Start of the TCS group relative to the TCSes in the RSC.
+ * @num_tcs:   Number of TCSes in this type.
+ * @ncpt:      Number of commands in each TCS.
+ * @req:       Requests that are sent from the TCS; only used for ACTIVE_ONLY
+ *             transfers (could be on a wake/sleep TCS if we are borrowing for
+ *             an ACTIVE_ONLY transfer).
+ *             Start: grab drv->lock, set req, set tcs_in_use, drop drv->lock,
+ *                    trigger
+ *             End: get irq, access req,
+ *                  grab drv->lock, clear tcs_in_use, drop drv->lock
+ * @slots:     Indicates which of @cmd_addr are occupied; only used for
+ *             SLEEP / WAKE TCSs.  Things are tightly packed in the
+ *             case that (ncpt < MAX_CMDS_PER_TCS).  That is if ncpt = 2 and
+ *             MAX_CMDS_PER_TCS = 16 then bit[2] = the first bit in 2nd TCS.
  */
 struct tcs_group {
 	struct rsc_drv *drv;
@@ -40,9 +47,7 @@ struct tcs_group {
 	u32 offset;
 	int num_tcs;
 	int ncpt;
-	spinlock_t lock;
 	const struct tcs_request *req[MAX_TCS_PER_TYPE];
-	u32 *cmd_cache;
 	DECLARE_BITMAP(slots, MAX_TCS_SLOTS);
 };
 
@@ -84,20 +89,32 @@ struct rpmh_ctrlr {
  * struct rsc_drv: the Direct Resource Voter (DRV) of the
  * Resource State Coordinator controller (RSC)
  *
- * @name:       controller identifier
- * @tcs_base:   start address of the TCS registers in this controller
- * @id:         instance id in the controller (Direct Resource Voter)
- * @num_tcs:    number of TCSes in this DRV
- * @tcs:        TCS groups
- * @tcs_in_use: s/w state of the TCS
- * @lock:       synchronize state of the controller
- * @client:     handle to the DRV's client.
+ * @name:               Controller identifier.
+ * @tcs_base:           Start address of the TCS registers in this controller.
+ * @id:                 Instance id in the controller (Direct Resource Voter).
+ * @num_tcs:            Number of TCSes in this DRV.
+ * @rsc_pm:             CPU PM notifier for controller.
+ *                      Used when solver mode is not present.
+ * @cpus_in_pm:         Number of CPUs not in idle power collapse.
+ *                      Used when solver mode is not present.
+ * @tcs:                TCS groups.
+ * @tcs_in_use:         S/W state of the TCS; only set for ACTIVE_ONLY
+ *                      transfers, but might show a sleep/wake TCS in use if
+ *                      it was borrowed for an active_only transfer.  You
+ *                      must hold the lock in this struct (AKA drv->lock) in
+ *                      order to update this.
+ * @lock:               Synchronize state of the controller.  If RPMH's cache
+ *                      lock will also be held, the order is: drv->lock then
+ *                      cache_lock.
+ * @client:             Handle to the DRV's client.
  */
 struct rsc_drv {
 	const char *name;
 	void __iomem *tcs_base;
 	int id;
 	int num_tcs;
+	struct notifier_block rsc_pm;
+	atomic_t cpus_in_pm;
 	struct tcs_group tcs[TCS_TYPE_NR];
 	DECLARE_BITMAP(tcs_in_use, MAX_TCS_NR);
 	spinlock_t lock;
@@ -107,7 +124,7 @@ struct rsc_drv {
 int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg);
 int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv,
 			     const struct tcs_request *msg);
-int rpmh_rsc_invalidate(struct rsc_drv *drv);
+void rpmh_rsc_invalidate(struct rsc_drv *drv);
 
 void rpmh_tx_done(const struct tcs_request *msg, int r);
 int rpmh_flush(struct rpmh_ctrlr *ctrlr);
diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c
index b71822131f59..076fd27f3081 100644
--- a/drivers/soc/qcom/rpmh-rsc.c
+++ b/drivers/soc/qcom/rpmh-rsc.c
@@ -6,9 +6,11 @@
 #define pr_fmt(fmt) "%s " fmt, KBUILD_MODNAME
 
 #include <linux/atomic.h>
+#include <linux/cpu_pm.h>
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/of.h>
@@ -30,21 +32,41 @@
 #define RSC_DRV_TCS_OFFSET		672
 #define RSC_DRV_CMD_OFFSET		20
 
-/* DRV Configuration Information Register */
+/* DRV HW Solver Configuration Information Register */
+#define DRV_SOLVER_CONFIG		0x04
+#define DRV_HW_SOLVER_MASK		1
+#define DRV_HW_SOLVER_SHIFT		24
+
+/* DRV TCS Configuration Information Register */
 #define DRV_PRNT_CHLD_CONFIG		0x0C
 #define DRV_NUM_TCS_MASK		0x3F
 #define DRV_NUM_TCS_SHIFT		6
 #define DRV_NCPT_MASK			0x1F
 #define DRV_NCPT_SHIFT			27
 
-/* Register offsets */
+/* Offsets for common TCS Registers, one bit per TCS */
 #define RSC_DRV_IRQ_ENABLE		0x00
 #define RSC_DRV_IRQ_STATUS		0x04
-#define RSC_DRV_IRQ_CLEAR		0x08
-#define RSC_DRV_CMD_WAIT_FOR_CMPL	0x10
+#define RSC_DRV_IRQ_CLEAR		0x08	/* w/o; write 1 to clear */
+
+/*
+ * Offsets for per TCS Registers.
+ *
+ * TCSes start at 0x10 from tcs_base and are stored one after another.
+ * Multiply tcs_id by RSC_DRV_TCS_OFFSET to find a given TCS and add one
+ * of the below to find a register.
+ */
+#define RSC_DRV_CMD_WAIT_FOR_CMPL	0x10	/* 1 bit per command */
 #define RSC_DRV_CONTROL			0x14
-#define RSC_DRV_STATUS			0x18
-#define RSC_DRV_CMD_ENABLE		0x1C
+#define RSC_DRV_STATUS			0x18	/* zero if tcs is busy */
+#define RSC_DRV_CMD_ENABLE		0x1C	/* 1 bit per command */
+
+/*
+ * Offsets for per command in a TCS.
+ *
+ * Commands (up to 16) start at 0x30 in a TCS; multiply command index
+ * by RSC_DRV_CMD_OFFSET and add one of the below to find a register.
+ */
 #define RSC_DRV_CMD_MSGID		0x30
 #define RSC_DRV_CMD_ADDR		0x34
 #define RSC_DRV_CMD_DATA		0x38
@@ -61,94 +83,179 @@
 #define CMD_STATUS_ISSUED		BIT(8)
 #define CMD_STATUS_COMPL		BIT(16)
 
-static u32 read_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id)
+/*
+ * Here's a high level overview of how all the registers in RPMH work
+ * together:
+ *
+ * - The main rpmh-rsc address is the base of a register space that can
+ *   be used to find overall configuration of the hardware
+ *   (DRV_PRNT_CHLD_CONFIG). Also found within the rpmh-rsc register
+ *   space are all the TCS blocks. The offset of the TCS blocks is
+ *   specified in the device tree by "qcom,tcs-offset" and used to
+ *   compute tcs_base.
+ * - TCS blocks come one after another. Type, count, and order are
+ *   specified by the device tree as "qcom,tcs-config".
+ * - Each TCS block has some registers, then space for up to 16 commands.
+ *   Note that though address space is reserved for 16 commands, fewer
+ *   might be present. See ncpt (num cmds per TCS).
+ *
+ * Here's a picture:
+ *
+ *  +---------------------------------------------------+
+ *  |RSC                                                |
+ *  | ctrl                                              |
+ *  |                                                   |
+ *  | Drvs:                                             |
+ *  | +-----------------------------------------------+ |
+ *  | |DRV0                                           | |
+ *  | | ctrl/config                                   | |
+ *  | | IRQ                                           | |
+ *  | |                                               | |
+ *  | | TCSes:                                        | |
+ *  | | +------------------------------------------+  | |
+ *  | | |TCS0  |  |  |  |  |  |  |  |  |  |  |  |  |  | |
+ *  | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15|  | |
+ *  | | |      |  |  |  |  |  |  |  |  |  |  |  |  |  | |
+ *  | | +------------------------------------------+  | |
+ *  | | +------------------------------------------+  | |
+ *  | | |TCS1  |  |  |  |  |  |  |  |  |  |  |  |  |  | |
+ *  | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15|  | |
+ *  | | |      |  |  |  |  |  |  |  |  |  |  |  |  |  | |
+ *  | | +------------------------------------------+  | |
+ *  | | +------------------------------------------+  | |
+ *  | | |TCS2  |  |  |  |  |  |  |  |  |  |  |  |  |  | |
+ *  | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15|  | |
+ *  | | |      |  |  |  |  |  |  |  |  |  |  |  |  |  | |
+ *  | | +------------------------------------------+  | |
+ *  | |                    ......                     | |
+ *  | +-----------------------------------------------+ |
+ *  | +-----------------------------------------------+ |
+ *  | |DRV1                                           | |
+ *  | | (same as DRV0)                                | |
+ *  | +-----------------------------------------------+ |
+ *  |                      ......                       |
+ *  +---------------------------------------------------+
+ */
+
+static inline void __iomem *
+tcs_reg_addr(const struct rsc_drv *drv, int reg, int tcs_id)
 {
-	return readl_relaxed(drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id +
-			     RSC_DRV_CMD_OFFSET * cmd_id);
+	return drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg;
 }
 
-static void write_tcs_cmd(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id,
-			  u32 data)
+static inline void __iomem *
+tcs_cmd_addr(const struct rsc_drv *drv, int reg, int tcs_id, int cmd_id)
 {
-	writel_relaxed(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id +
-		       RSC_DRV_CMD_OFFSET * cmd_id);
+	return tcs_reg_addr(drv, reg, tcs_id) + RSC_DRV_CMD_OFFSET * cmd_id;
 }
 
-static void write_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id, u32 data)
+static u32 read_tcs_cmd(const struct rsc_drv *drv, int reg, int tcs_id,
+			int cmd_id)
 {
-	writel_relaxed(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id);
+	return readl_relaxed(tcs_cmd_addr(drv, reg, tcs_id, cmd_id));
 }
 
-static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id,
-			       u32 data)
+static u32 read_tcs_reg(const struct rsc_drv *drv, int reg, int tcs_id)
 {
-	writel(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id);
-	for (;;) {
-		if (data == readl(drv->tcs_base + reg +
-				  RSC_DRV_TCS_OFFSET * tcs_id))
-			break;
-		udelay(1);
-	}
+	return readl_relaxed(tcs_reg_addr(drv, reg, tcs_id));
 }
 
-static bool tcs_is_free(struct rsc_drv *drv, int tcs_id)
+static void write_tcs_cmd(const struct rsc_drv *drv, int reg, int tcs_id,
+			  int cmd_id, u32 data)
 {
-	return !test_bit(tcs_id, drv->tcs_in_use) &&
-	       read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id, 0);
+	writel_relaxed(data, tcs_cmd_addr(drv, reg, tcs_id, cmd_id));
 }
 
-static struct tcs_group *get_tcs_of_type(struct rsc_drv *drv, int type)
+static void write_tcs_reg(const struct rsc_drv *drv, int reg, int tcs_id,
+			  u32 data)
 {
-	return &drv->tcs[type];
+	writel_relaxed(data, tcs_reg_addr(drv, reg, tcs_id));
 }
 
-static int tcs_invalidate(struct rsc_drv *drv, int type)
+static void write_tcs_reg_sync(const struct rsc_drv *drv, int reg, int tcs_id,
+			       u32 data)
 {
-	int m;
-	struct tcs_group *tcs;
+	u32 new_data;
 
-	tcs = get_tcs_of_type(drv, type);
+	writel(data, tcs_reg_addr(drv, reg, tcs_id));
+	if (readl_poll_timeout_atomic(tcs_reg_addr(drv, reg, tcs_id), new_data,
+				      new_data == data, 1, USEC_PER_SEC))
+		pr_err("%s: error writing %#x to %d:%#x\n", drv->name,
+		       data, tcs_id, reg);
+}
 
-	spin_lock(&tcs->lock);
-	if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS)) {
-		spin_unlock(&tcs->lock);
-		return 0;
-	}
+/**
+ * tcs_is_free() - Return if a TCS is totally free.
+ * @drv:    The RSC controller.
+ * @tcs_id: The global ID of this TCS.
+ *
+ * Returns true if nobody has claimed this TCS (by setting tcs_in_use).
+ *
+ * Context: Must be called with the drv->lock held.
+ *
+ * Return: true if the given TCS is free.
+ */
+static bool tcs_is_free(struct rsc_drv *drv, int tcs_id)
+{
+	return !test_bit(tcs_id, drv->tcs_in_use);
+}
+
+/**
+ * tcs_invalidate() - Invalidate all TCSes of the given type (sleep or wake).
+ * @drv:  The RSC controller.
+ * @type: SLEEP_TCS or WAKE_TCS
+ *
+ * This will clear the "slots" variable of the given tcs_group and also
+ * tell the hardware to forget about all entries.
+ *
+ * The caller must ensure that no other RPMH actions are happening when this
+ * function is called, since otherwise the device may immediately become
+ * used again even before this function exits.
+ */
+static void tcs_invalidate(struct rsc_drv *drv, int type)
+{
+	int m;
+	struct tcs_group *tcs = &drv->tcs[type];
+
+	/* Caller ensures nobody else is running so no lock */
+	if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS))
+		return;
 
 	for (m = tcs->offset; m < tcs->offset + tcs->num_tcs; m++) {
-		if (!tcs_is_free(drv, m)) {
-			spin_unlock(&tcs->lock);
-			return -EAGAIN;
-		}
 		write_tcs_reg_sync(drv, RSC_DRV_CMD_ENABLE, m, 0);
 		write_tcs_reg_sync(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, m, 0);
 	}
 	bitmap_zero(tcs->slots, MAX_TCS_SLOTS);
-	spin_unlock(&tcs->lock);
-
-	return 0;
 }
 
 /**
- * rpmh_rsc_invalidate - Invalidate sleep and wake TCSes
+ * rpmh_rsc_invalidate() - Invalidate sleep and wake TCSes.
+ * @drv: The RSC controller.
  *
- * @drv: the RSC controller
+ * The caller must ensure that no other RPMH actions are happening when this
+ * function is called, since otherwise the device may immediately become
+ * used again even before this function exits.
  */
-int rpmh_rsc_invalidate(struct rsc_drv *drv)
+void rpmh_rsc_invalidate(struct rsc_drv *drv)
 {
-	int ret;
-
-	ret = tcs_invalidate(drv, SLEEP_TCS);
-	if (!ret)
-		ret = tcs_invalidate(drv, WAKE_TCS);
-
-	return ret;
+	tcs_invalidate(drv, SLEEP_TCS);
+	tcs_invalidate(drv, WAKE_TCS);
 }
 
+/**
+ * get_tcs_for_msg() - Get the tcs_group used to send the given message.
+ * @drv: The RSC controller.
+ * @msg: The message we want to send.
+ *
+ * This is normally pretty straightforward except if we are trying to send
+ * an ACTIVE_ONLY message but don't have any active_only TCSes.
+ *
+ * Return: A pointer to a tcs_group or an ERR_PTR.
+ */
 static struct tcs_group *get_tcs_for_msg(struct rsc_drv *drv,
 					 const struct tcs_request *msg)
 {
-	int type, ret;
+	int type;
 	struct tcs_group *tcs;
 
 	switch (msg->state) {
@@ -168,24 +275,33 @@ static struct tcs_group *get_tcs_for_msg(struct rsc_drv *drv,
 	/*
 	 * If we are making an active request on a RSC that does not have a
 	 * dedicated TCS for active state use, then re-purpose a wake TCS to
-	 * send active votes.
-	 * NOTE: The driver must be aware that this RSC does not have a
-	 * dedicated AMC, and therefore would invalidate the sleep and wake
-	 * TCSes before making an active state request.
+	 * send active votes. This is safe because we ensure any active-only
+	 * transfers have finished before we use it (maybe by running from
+	 * the last CPU in PM code).
 	 */
-	tcs = get_tcs_of_type(drv, type);
-	if (msg->state == RPMH_ACTIVE_ONLY_STATE && !tcs->num_tcs) {
-		tcs = get_tcs_of_type(drv, WAKE_TCS);
-		if (tcs->num_tcs) {
-			ret = rpmh_rsc_invalidate(drv);
-			if (ret)
-				return ERR_PTR(ret);
-		}
-	}
+	tcs = &drv->tcs[type];
+	if (msg->state == RPMH_ACTIVE_ONLY_STATE && !tcs->num_tcs)
+		tcs = &drv->tcs[WAKE_TCS];
 
 	return tcs;
 }
 
+/**
+ * get_req_from_tcs() - Get a stashed request that was xfering on the given TCS.
+ * @drv:    The RSC controller.
+ * @tcs_id: The global ID of this TCS.
+ *
+ * For ACTIVE_ONLY transfers we want to call back into the client when the
+ * transfer finishes. To do this we need the "request" that the client
+ * originally provided us. This function grabs the request that we stashed
+ * when we started the transfer.
+ *
+ * This only makes sense for ACTIVE_ONLY transfers since those are the only
+ * ones we track sending (the only ones we enable interrupts for and the only
+ * ones we call back to the client for).
+ *
+ * Return: The stashed request.
+ */
 static const struct tcs_request *get_req_from_tcs(struct rsc_drv *drv,
 						  int tcs_id)
 {
@@ -202,7 +318,76 @@ static const struct tcs_request *get_req_from_tcs(struct rsc_drv *drv,
 }
 
 /**
- * tcs_tx_done: TX Done interrupt handler
+ * __tcs_set_trigger() - Start xfer on a TCS or unset trigger on a borrowed TCS
+ * @drv:     The controller.
+ * @tcs_id:  The global ID of this TCS.
+ * @trigger: If true then untrigger/retrigger. If false then just untrigger.
+ *
+ * In the normal case we only ever call with "trigger=true" to start a
+ * transfer. That will un-trigger/disable the TCS from the last transfer
+ * then trigger/enable for this transfer.
+ *
+ * If we borrowed a wake TCS for an active-only transfer we'll also call
+ * this function with "trigger=false" to just do the un-trigger/disable
+ * before using the TCS for wake purposes again.
+ *
+ * Note that the AP is only in charge of triggering active-only transfers.
+ * The AP never triggers sleep/wake values using this function.
+ */
+static void __tcs_set_trigger(struct rsc_drv *drv, int tcs_id, bool trigger)
+{
+	u32 enable;
+
+	/*
+	 * HW req: Clear the DRV_CONTROL and enable TCS again
+	 * While clearing ensure that the AMC mode trigger is cleared
+	 * and then the mode enable is cleared.
+	 */
+	enable = read_tcs_reg(drv, RSC_DRV_CONTROL, tcs_id);
+	enable &= ~TCS_AMC_MODE_TRIGGER;
+	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
+	enable &= ~TCS_AMC_MODE_ENABLE;
+	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
+
+	if (trigger) {
+		/* Enable the AMC mode on the TCS and then trigger the TCS */
+		enable = TCS_AMC_MODE_ENABLE;
+		write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
+		enable |= TCS_AMC_MODE_TRIGGER;
+		write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
+	}
+}
+
+/**
+ * enable_tcs_irq() - Enable or disable interrupts on the given TCS.
+ * @drv:     The controller.
+ * @tcs_id:  The global ID of this TCS.
+ * @enable:  If true then enable; if false then disable
+ *
+ * We only ever call this when we borrow a wake TCS for an active-only
+ * transfer. For active-only TCSes interrupts are always left enabled.
+ */
+static void enable_tcs_irq(struct rsc_drv *drv, int tcs_id, bool enable)
+{
+	u32 data;
+
+	data = readl_relaxed(drv->tcs_base + RSC_DRV_IRQ_ENABLE);
+	if (enable)
+		data |= BIT(tcs_id);
+	else
+		data &= ~BIT(tcs_id);
+	writel_relaxed(data, drv->tcs_base + RSC_DRV_IRQ_ENABLE);
+}
+
+/**
+ * tcs_tx_done() - TX Done interrupt handler.
+ * @irq: The IRQ number (ignored).
+ * @p:   Pointer to "struct rsc_drv".
+ *
+ * Called for ACTIVE_ONLY transfers (those are the only ones we enable the
+ * IRQ for) when a transfer is done.
+ *
+ * Return: IRQ_HANDLED
  */
 static irqreturn_t tcs_tx_done(int irq, void *p)
 {
@@ -212,7 +397,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p)
 	const struct tcs_request *req;
 	struct tcs_cmd *cmd;
 
-	irq_status = read_tcs_reg(drv, RSC_DRV_IRQ_STATUS, 0, 0);
+	irq_status = readl_relaxed(drv->tcs_base + RSC_DRV_IRQ_STATUS);
 
 	for_each_set_bit(i, &irq_status, BITS_PER_LONG) {
 		req = get_req_from_tcs(drv, i);
@@ -226,7 +411,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p)
 			u32 sts;
 
 			cmd = &req->cmds[j];
-			sts = read_tcs_reg(drv, RSC_DRV_CMD_STATUS, i, j);
+			sts = read_tcs_cmd(drv, RSC_DRV_CMD_STATUS, i, j);
 			if (!(sts & CMD_STATUS_ISSUED) ||
 			   ((req->wait_for_compl || cmd->wait) &&
 			   !(sts & CMD_STATUS_COMPL))) {
@@ -237,13 +422,28 @@ static irqreturn_t tcs_tx_done(int irq, void *p)
 		}
 
 		trace_rpmh_tx_done(drv, i, req, err);
+
+		/*
+		 * If wake tcs was re-purposed for sending active
+		 * votes, clear AMC trigger & enable modes and
+		 * disable interrupt for this TCS
+		 */
+		if (!drv->tcs[ACTIVE_TCS].num_tcs)
+			__tcs_set_trigger(drv, i, false);
 skip:
 		/* Reclaim the TCS */
 		write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, i, 0);
 		write_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, i, 0);
-		write_tcs_reg(drv, RSC_DRV_IRQ_CLEAR, 0, BIT(i));
+		writel_relaxed(BIT(i), drv->tcs_base + RSC_DRV_IRQ_CLEAR);
 		spin_lock(&drv->lock);
 		clear_bit(i, drv->tcs_in_use);
+		/*
+		 * Disable interrupt for WAKE TCS to avoid being
+		 * spammed with interrupts coming when the solver
+		 * sends its wake votes.
+		 */
+		if (!drv->tcs[ACTIVE_TCS].num_tcs)
+			enable_tcs_irq(drv, i, false);
 		spin_unlock(&drv->lock);
 		if (req)
 			rpmh_tx_done(req, err);
@@ -252,6 +452,16 @@ skip:
 	return IRQ_HANDLED;
 }
 
+/**
+ * __tcs_buffer_write() - Write to TCS hardware from a request; don't trigger.
+ * @drv:    The controller.
+ * @tcs_id: The global ID of this TCS.
+ * @cmd_id: The index within the TCS to start writing.
+ * @msg:    The message we want to send, which will contain several addr/data
+ *          pairs to program (but few enough that they all fit in one TCS).
+ *
+ * This is used for all types of transfers (active, sleep, and wake).
+ */
 static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id,
 			       const struct tcs_request *msg)
 {
@@ -265,7 +475,7 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id,
 	cmd_msgid |= msg->wait_for_compl ? CMD_MSGID_RESP_REQ : 0;
 	cmd_msgid |= CMD_MSGID_WRITE;
 
-	cmd_complete = read_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id, 0);
+	cmd_complete = read_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id);
 
 	for (i = 0, j = cmd_id; i < msg->num_cmds; i++, j++) {
 		cmd = &msg->cmds[i];
@@ -281,32 +491,30 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id,
 	}
 
 	write_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id, cmd_complete);
-	cmd_enable |= read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, 0);
+	cmd_enable |= read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id);
 	write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, cmd_enable);
 }
 
-static void __tcs_trigger(struct rsc_drv *drv, int tcs_id)
-{
-	u32 enable;
-
-	/*
-	 * HW req: Clear the DRV_CONTROL and enable TCS again
-	 * While clearing ensure that the AMC mode trigger is cleared
-	 * and then the mode enable is cleared.
-	 */
-	enable = read_tcs_reg(drv, RSC_DRV_CONTROL, tcs_id, 0);
-	enable &= ~TCS_AMC_MODE_TRIGGER;
-	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
-	enable &= ~TCS_AMC_MODE_ENABLE;
-	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
-
-	/* Enable the AMC mode on the TCS and then trigger the TCS */
-	enable = TCS_AMC_MODE_ENABLE;
-	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
-	enable |= TCS_AMC_MODE_TRIGGER;
-	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
-}
-
+/**
+ * check_for_req_inflight() - Look to see if conflicting cmds are in flight.
+ * @drv: The controller.
+ * @tcs: A pointer to the tcs_group used for ACTIVE_ONLY transfers.
+ * @msg: The message we want to send, which will contain several addr/data
+ *       pairs to program (but few enough that they all fit in one TCS).
+ *
+ * This will walk through the TCSes in the group and check if any of them
+ * appear to be sending to addresses referenced in the message. If it finds
+ * one it'll return -EBUSY.
+ *
+ * Only for use for active-only transfers.
+ *
+ * Must be called with the drv->lock held since that protects tcs_in_use.
+ *
+ * Return: 0 if nothing in flight or -EBUSY if we should try again later.
+ *         The caller must re-enable interrupts between tries since that's
+ *         the only way tcs_is_free() will ever return true and the only way
+ *         RSC_DRV_CMD_ENABLE will ever be cleared.
+ */
 static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs,
 				  const struct tcs_request *msg)
 {
@@ -319,10 +527,10 @@ static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs,
 		if (tcs_is_free(drv, tcs_id))
 			continue;
 
-		curr_enabled = read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, 0);
+		curr_enabled = read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id);
 
 		for_each_set_bit(j, &curr_enabled, MAX_CMDS_PER_TCS) {
-			addr = read_tcs_reg(drv, RSC_DRV_CMD_ADDR, tcs_id, j);
+			addr = read_tcs_cmd(drv, RSC_DRV_CMD_ADDR, tcs_id, j);
 			for (k = 0; k < msg->num_cmds; k++) {
 				if (addr == msg->cmds[k].addr)
 					return -EBUSY;
@@ -333,6 +541,15 @@ static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs,
 	return 0;
 }
 
+/**
+ * find_free_tcs() - Find free tcs in the given tcs_group; only for active.
+ * @tcs: A pointer to the active-only tcs_group (or the wake tcs_group if
+ *       we borrowed it because there are zero active-only ones).
+ *
+ * Must be called with the drv->lock held since that protects tcs_in_use.
+ *
+ * Return: The first tcs that's free.
+ */
 static int find_free_tcs(struct tcs_group *tcs)
 {
 	int i;
@@ -345,6 +562,20 @@ static int find_free_tcs(struct tcs_group *tcs)
 	return -EBUSY;
 }
 
+/**
+ * tcs_write() - Store messages into a TCS right now, or return -EBUSY.
+ * @drv: The controller.
+ * @msg: The data to be sent.
+ *
+ * Grabs a TCS for ACTIVE_ONLY transfers and writes the messages to it.
+ *
+ * If there are no free TCSes for ACTIVE_ONLY transfers or if a command for
+ * the same address is already transferring returns -EBUSY which means the
+ * client should retry shortly.
+ *
+ * Return: 0 on success, -EBUSY if client should retry, or an error.
+ *         Client should have interrupts enabled for a bit before retrying.
+ */
 static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg)
 {
 	struct tcs_group *tcs;
@@ -356,57 +587,77 @@ static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg)
 	if (IS_ERR(tcs))
 		return PTR_ERR(tcs);
 
-	spin_lock_irqsave(&tcs->lock, flags);
-	spin_lock(&drv->lock);
+	spin_lock_irqsave(&drv->lock, flags);
 	/*
 	 * The h/w does not like if we send a request to the same address,
 	 * when one is already in-flight or being processed.
 	 */
 	ret = check_for_req_inflight(drv, tcs, msg);
-	if (ret) {
-		spin_unlock(&drv->lock);
-		goto done_write;
-	}
+	if (ret)
+		goto unlock;
 
-	tcs_id = find_free_tcs(tcs);
-	if (tcs_id < 0) {
-		ret = tcs_id;
-		spin_unlock(&drv->lock);
-		goto done_write;
-	}
+	ret = find_free_tcs(tcs);
+	if (ret < 0)
+		goto unlock;
+	tcs_id = ret;
 
 	tcs->req[tcs_id - tcs->offset] = msg;
 	set_bit(tcs_id, drv->tcs_in_use);
-	spin_unlock(&drv->lock);
+	if (msg->state == RPMH_