msm: qdss: coresight PFT tracing support

Initial version of the PFT trace driver.

CRs-Fixed: 305958
Signed-off-by: Pratik Patel <pratikp@codeaurora.org>
diff --git a/arch/arm/mach-msm/qdss-ptm.c b/arch/arm/mach-msm/qdss-ptm.c
new file mode 100644
index 0000000..ffd0b8d
--- /dev/null
+++ b/arch/arm/mach-msm/qdss-ptm.c
@@ -0,0 +1,1021 @@
+/* Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/smp.h>
+#include <linux/percpu.h>
+#include <linux/wakelock.h>
+#include <linux/pm_qos_params.h>
+#include <linux/clk.h>
+#include <asm/atomic.h>
+
+#include "qdss.h"
+
+#define ptm_writel(ptm, cpu, val, off)	\
+			__raw_writel((val), ptm.base + (SZ_4K * cpu) + off)
+#define ptm_readl(ptm, cpu, off)	\
+			__raw_readl(ptm.base + (SZ_4K * cpu) + off)
+
+/*
+ * Device registers:
+ * 0x000 - 0x2FC: Trace		registers
+ * 0x300 - 0x314: Management	registers
+ * 0x318 - 0xEFC: Trace		registers
+ *
+ * Coresight registers
+ * 0xF00 - 0xF9C: Management	registers
+ * 0xFA0 - 0xFA4: Management	registers in PFTv1.0
+ *		  Trace		registers in PFTv1.1
+ * 0xFA8 - 0xFFC: Management	registers
+ */
+
+/* Trace registers (0x000-0x2FC) */
+#define ETMCR			(0x000)
+#define ETMCCR			(0x004)
+#define ETMTRIGGER		(0x008)
+#define ETMSR			(0x010)
+#define ETMSCR			(0x014)
+#define ETMTSSCR		(0x018)
+#define ETMTEEVR		(0x020)
+#define ETMTECR1		(0x024)
+#define ETMFFLR			(0x02C)
+#define ETMACVRn(n)		(0x040 + (n * 4))
+#define ETMACTRn(n)		(0x080 + (n * 4))
+#define ETMCNTRLDVRn(n)		(0x140 + (n * 4))
+#define ETMCNTENRn(n)		(0x150 + (n * 4))
+#define ETMCNTRLDEVRn(n)	(0x160 + (n * 4))
+#define ETMCNTVRn(n)		(0x170 + (n * 4))
+#define ETMSQ12EVR		(0x180)
+#define ETMSQ21EVR		(0x184)
+#define ETMSQ23EVR		(0x188)
+#define ETMSQ32EVR		(0x18C)
+#define ETMSQ13EVR		(0x190)
+#define ETMSQ31EVR		(0x194)
+#define ETMSQR			(0x19C)
+#define ETMEXTOUTEVRn(n)	(0x1A0 + (n * 4))
+#define ETMCIDCVRn(n)		(0x1B0 + (n * 4))
+#define ETMCIDCMR		(0x1BC)
+#define ETMIMPSPEC0		(0x1C0)
+#define ETMIMPSPEC1		(0x1C4)
+#define ETMIMPSPEC2		(0x1C8)
+#define ETMIMPSPEC3		(0x1CC)
+#define ETMIMPSPEC4		(0x1D0)
+#define ETMIMPSPEC5		(0x1D4)
+#define ETMIMPSPEC6		(0x1D8)
+#define ETMIMPSPEC7		(0x1DC)
+#define ETMSYNCFR		(0x1E0)
+#define ETMIDR			(0x1E4)
+#define ETMCCER			(0x1E8)
+#define ETMEXTINSELR		(0x1EC)
+#define ETMTESSEICR		(0x1F0)
+#define ETMEIBCR		(0x1F4)
+#define ETMTSEVR		(0x1F8)
+#define ETMAUXCR		(0x1FC)
+#define ETMTRACEIDR		(0x200)
+#define ETMVMIDCVR		(0x204)
+/* Management registers (0x300-0x314) */
+#define ETMOSLAR		(0x300)
+#define ETMOSLSR		(0x304)
+#define ETMOSSRR		(0x308)
+#define ETMPDCR			(0x310)
+#define ETMPDSR			(0x314)
+
+
+#define PTM_LOCK(cpu)							\
+do {									\
+	mb();								\
+	ptm_writel(ptm, cpu, MAGIC2, CS_LAR);				\
+} while (0)
+#define PTM_UNLOCK(cpu)							\
+do {									\
+	ptm_writel(ptm, cpu, MAGIC1, CS_LAR);				\
+	mb();								\
+} while (0)
+
+#define PTM_OS_LOCK(cpu)						\
+do {									\
+	ptm_writel(ptm, cpu, MAGIC1, ETMOSLAR);				\
+	mb();								\
+} while (0)
+#define PTM_OS_UNLOCK(cpu)						\
+do {									\
+	ptm_writel(ptm, cpu, MAGIC2, ETMOSLAR);				\
+	mb();								\
+} while (0)
+
+#define MAX_TRACE_REGS		(78)
+#define MAX_STATE_SIZE		(MAX_TRACE_REGS * num_possible_cpus())
+
+/* Forward declarations */
+static void ptm_cfg_rw_init(void);
+
+static int trace_on_boot;
+module_param_named(
+	trace_on_boot, trace_on_boot, int, S_IRUGO
+);
+
+struct ptm_config {
+	/* read only config registers */
+	uint32_t	config_code;
+	/* derived values */
+	uint8_t		nr_addr_comp;
+	uint8_t		nr_cntr;
+	uint8_t		nr_ext_input;
+	uint8_t		nr_ext_output;
+	uint8_t		nr_context_id_comp;
+
+	uint32_t	config_code_extn;
+	/* derived values */
+	uint8_t		nr_extnd_ext_input_sel;
+	uint8_t		nr_instr_resources;
+
+	uint32_t	system_config;
+	/* derived values */
+	uint8_t		fifofull_supported;
+	uint8_t		nr_procs_supported;
+
+	/* read-write registers */
+	uint32_t	main_control;
+	uint32_t	trigger_event;
+	uint32_t	te_start_stop_control;
+	uint32_t	te_event;
+	uint32_t	te_control;
+	uint32_t	fifofull_level;
+	uint32_t	addr_comp_value[16];
+	uint32_t	addr_comp_access_type[16];
+	uint32_t	cntr_reload_value[4];
+	uint32_t	cntr_enable_event[4];
+	uint32_t	cntr_reload_event[4];
+	uint32_t	cntr_value[4];
+	uint32_t	seq_state_12_event;
+	uint32_t	seq_state_21_event;
+	uint32_t	seq_state_23_event;
+	uint32_t	seq_state_32_event;
+	uint32_t	seq_state_13_event;
+	uint32_t	seq_state_31_event;
+	uint32_t	current_seq_state;
+	uint32_t	ext_output_event[4];
+	uint32_t	context_id_comp_value[3];
+	uint32_t	context_id_comp_mask;
+	uint32_t	sync_freq;
+	uint32_t	extnd_ext_input_sel;
+	uint32_t	ts_event;
+	uint32_t	aux_control;
+	uint32_t	coresight_trace_id;
+	uint32_t	vmid_comp_value;
+};
+
+struct ptm_ctx {
+	struct ptm_config		cfg;
+	void __iomem			*base;
+	uint32_t			*state;
+	bool				trace_enabled;
+	int				*cpu_restore;
+	struct wake_lock		wake_lock;
+	struct pm_qos_request_list	qos_req;
+	atomic_t			in_use;
+	struct device			*dev;
+	struct clk			*qdss_at_clk;
+	struct clk			*qdss_pclkdbg_clk;
+	struct clk			*qdss_pclk;
+	struct clk			*qdss_traceclkin_clk;
+	struct clk			*qdss_tsctr_clk;
+};
+
+static struct ptm_ctx ptm;
+
+/* Memory mapped writes to clear os lock don't work */
+static void ptm_os_unlock(void *unused)
+{
+	unsigned long value = 0x0;
+
+	asm("mcr p14, 1, %0, c1, c0, 4\n\t" : : "r" (value));
+	asm("isb\n\t");
+}
+
+static int ptm_clock_enable(void)
+{
+	int ret;
+
+	ret = clk_enable(ptm.qdss_at_clk);
+	if (WARN(ret, "qdss_at_clk not enabled (%d)\n", ret))
+		goto err;
+
+	ret = clk_enable(ptm.qdss_pclkdbg_clk);
+	if (WARN(ret, "qdss_pclkdbg_clk not enabled (%d)\n", ret))
+		goto err_pclkdbg;
+
+	ret = clk_enable(ptm.qdss_pclk);
+	if (WARN(ret, "qdss_pclk not enabled (%d)\n", ret))
+		goto err_pclk;
+
+	ret = clk_enable(ptm.qdss_traceclkin_clk);
+	if (WARN(ret, "qdss_traceclkin_clk not enabled (%d)\n", ret))
+		goto err_traceclkin;
+
+	ret = clk_enable(ptm.qdss_tsctr_clk);
+	if (WARN(ret, "qdss_tsctr_clk not enabled (%d)\n", ret))
+		goto err_tsctr;
+
+	return 0;
+
+err_tsctr:
+	clk_disable(ptm.qdss_traceclkin_clk);
+err_traceclkin:
+	clk_disable(ptm.qdss_pclk);
+err_pclk:
+	clk_disable(ptm.qdss_pclkdbg_clk);
+err_pclkdbg:
+	clk_disable(ptm.qdss_at_clk);
+err:
+	return ret;
+}
+
+static void ptm_clock_disable(void)
+{
+	clk_disable(ptm.qdss_tsctr_clk);
+	clk_disable(ptm.qdss_traceclkin_clk);
+	clk_disable(ptm.qdss_pclk);
+	clk_disable(ptm.qdss_pclkdbg_clk);
+	clk_disable(ptm.qdss_at_clk);
+}
+
+static void ptm_set_powerdown(int cpu)
+{
+	uint32_t etmcr;
+
+	etmcr = ptm_readl(ptm, cpu, ETMCR);
+	etmcr |= BIT(0);
+	ptm_writel(ptm, cpu, etmcr, ETMCR);
+}
+
+static void ptm_clear_powerdown(int cpu)
+{
+	uint32_t etmcr;
+
+	etmcr = ptm_readl(ptm, cpu, ETMCR);
+	etmcr &= ~BIT(0);
+	ptm_writel(ptm, cpu, etmcr, ETMCR);
+}
+
+static void ptm_set_prog(int cpu)
+{
+	uint32_t etmcr;
+	int count;
+
+	etmcr = ptm_readl(ptm, cpu, ETMCR);
+	etmcr |= BIT(10);
+	ptm_writel(ptm, cpu, etmcr, ETMCR);
+
+	for (count = TIMEOUT_US; BVAL(ptm_readl(ptm, cpu, ETMSR), 1) != 1
+				&& count > 0; count--)
+		udelay(1);
+	WARN(count == 0, "timeout while setting prog bit\n");
+}
+
+static void ptm_clear_prog(int cpu)
+{
+	uint32_t etmcr;
+	int count;
+
+	etmcr = ptm_readl(ptm, cpu, ETMCR);
+	etmcr &= ~BIT(10);
+	ptm_writel(ptm, cpu, etmcr, ETMCR);
+
+	for (count = TIMEOUT_US; BVAL(ptm_readl(ptm, cpu, ETMSR), 1) != 0
+				&& count > 0; count--)
+		udelay(1);
+	WARN(count == 0, "timeout while clearing prog bit\n");
+}
+
+static void __ptm_trace_enable(void)
+{
+	int i, cpu;
+
+	for_each_online_cpu(cpu) {
+		PTM_UNLOCK(cpu);
+		ptm_clear_powerdown(cpu);
+		ptm_set_prog(cpu);
+
+		ptm_writel(ptm, cpu, ptm.cfg.main_control | BIT(10), ETMCR);
+		ptm_writel(ptm, cpu, ptm.cfg.trigger_event, ETMTRIGGER);
+		ptm_writel(ptm, cpu, ptm.cfg.te_start_stop_control, ETMTSSCR);
+		ptm_writel(ptm, cpu, ptm.cfg.te_event, ETMTEEVR);
+		ptm_writel(ptm, cpu, ptm.cfg.te_control, ETMTECR1);
+		ptm_writel(ptm, cpu, ptm.cfg.fifofull_level, ETMFFLR);
+		for (i = 0; i < ptm.cfg.nr_addr_comp; i++) {
+			ptm_writel(ptm, cpu, ptm.cfg.addr_comp_value[i],
+							ETMACVRn(i));
+			ptm_writel(ptm, cpu, ptm.cfg.addr_comp_access_type[i],
+							ETMACTRn(i));
+		}
+		for (i = 0; i < ptm.cfg.nr_cntr; i++) {
+			ptm_writel(ptm, cpu, ptm.cfg.cntr_reload_value[i],
+							ETMCNTRLDVRn(i));
+			ptm_writel(ptm, cpu, ptm.cfg.cntr_enable_event[i],
+							ETMCNTENRn(i));
+			ptm_writel(ptm, cpu, ptm.cfg.cntr_reload_event[i],
+							ETMCNTRLDEVRn(i));
+			ptm_writel(ptm, cpu, ptm.cfg.cntr_value[i],
+							ETMCNTVRn(i));
+		}
+		ptm_writel(ptm, cpu, ptm.cfg.seq_state_12_event, ETMSQ12EVR);
+		ptm_writel(ptm, cpu, ptm.cfg.seq_state_21_event, ETMSQ21EVR);
+		ptm_writel(ptm, cpu, ptm.cfg.seq_state_23_event, ETMSQ23EVR);
+		ptm_writel(ptm, cpu, ptm.cfg.seq_state_32_event, ETMSQ32EVR);
+		ptm_writel(ptm, cpu, ptm.cfg.seq_state_13_event, ETMSQ13EVR);
+		ptm_writel(ptm, cpu, ptm.cfg.seq_state_31_event, ETMSQ31EVR);
+		ptm_writel(ptm, cpu, ptm.cfg.current_seq_state, ETMSQR);
+		for (i = 0; i < ptm.cfg.nr_ext_output; i++)
+			ptm_writel(ptm, cpu, ptm.cfg.ext_output_event[i],
+							ETMEXTOUTEVRn(i));
+		for (i = 0; i < ptm.cfg.nr_context_id_comp; i++)
+			ptm_writel(ptm, cpu, ptm.cfg.context_id_comp_value[i],
+							ETMCIDCVRn(i));
+		ptm_writel(ptm, cpu, ptm.cfg.context_id_comp_mask, ETMCIDCMR);
+		ptm_writel(ptm, cpu, ptm.cfg.sync_freq, ETMSYNCFR);
+		ptm_writel(ptm, cpu, ptm.cfg.extnd_ext_input_sel, ETMEXTINSELR);
+		ptm_writel(ptm, cpu, ptm.cfg.ts_event, ETMTSEVR);
+		ptm_writel(ptm, cpu, ptm.cfg.aux_control, ETMAUXCR);
+		ptm_writel(ptm, cpu, ptm.cfg.vmid_comp_value, ETMVMIDCVR);
+
+		ptm_clear_prog(cpu);
+		PTM_LOCK(cpu);
+	}
+}
+
+static int ptm_trace_enable(void)
+{
+	int ret;
+
+	ret = ptm_clock_enable();
+	if (ret)
+		return ret;
+
+	wake_lock(&ptm.wake_lock);
+	/* 1. causes all cpus to come out of idle PC
+	 * 2. prevents idle PC until save restore flag is enabled atomically
+	 */
+	pm_qos_update_request(&ptm.qos_req, 0);
+
+	etb_disable();
+	tpiu_disable();
+	/* enable ETB first to avoid loosing any trace data */
+	etb_enable();
+	funnel_enable(0x0, 0x3);
+	ptm_os_unlock(NULL);
+	smp_call_function(ptm_os_unlock, NULL, 1);
+	__ptm_trace_enable();
+
+	ptm.trace_enabled = true;
+
+	pm_qos_update_request(&ptm.qos_req, PM_QOS_DEFAULT_VALUE);
+	wake_unlock(&ptm.wake_lock);
+
+	return 0;
+}
+
+static void __ptm_trace_disable(void)
+{
+	int cpu;
+
+	for_each_online_cpu(cpu) {
+		PTM_UNLOCK(cpu);
+		ptm_set_prog(cpu);
+
+		/* program trace enable to low by using always false event */
+		ptm_writel(ptm, cpu, 0x6F | BIT(14), ETMTEEVR);
+
+		ptm_set_powerdown(cpu);
+		PTM_LOCK(cpu);
+	}
+}
+
+static void ptm_trace_disable(void)
+{
+	int cpu;
+
+	wake_lock(&ptm.wake_lock);
+	/* 1. causes all cpus to come out of idle PC
+	 * 2. prevents idle PC until save restore flag is disabled atomically
+	 */
+	pm_qos_update_request(&ptm.qos_req, 0);
+
+	ptm_os_unlock(NULL);
+	smp_call_function(ptm_os_unlock, NULL, 1);
+	__ptm_trace_disable();
+	etb_dump();
+	etb_disable();
+	funnel_disable(0x0, 0x3);
+
+	ptm.trace_enabled = false;
+
+	for_each_online_cpu(cpu)
+		*per_cpu_ptr(ptm.cpu_restore, cpu) = 0;
+
+	pm_qos_update_request(&ptm.qos_req, PM_QOS_DEFAULT_VALUE);
+	wake_unlock(&ptm.wake_lock);
+
+	ptm_clock_disable();
+}
+
+static int ptm_open(struct inode *inode, struct file *file)
+{
+	if (atomic_cmpxchg(&ptm.in_use, 0, 1))
+		return -EBUSY;
+
+	dev_dbg(ptm.dev, "%s: successfully opened\n", __func__);
+	return 0;
+}
+
+static void ptm_range_filter(char range, uint32_t reg1,
+				uint32_t addr1, uint32_t reg2, uint32_t addr2)
+{
+	ptm.cfg.addr_comp_value[reg1] = addr1;
+	ptm.cfg.addr_comp_value[reg2] = addr2;
+
+	ptm.cfg.te_control |= (1 << (reg1/2));
+	if (range == 'i')
+		ptm.cfg.te_control &= ~BIT(24);
+	else if (range == 'e')
+		ptm.cfg.te_control |= BIT(24);
+}
+
+static void ptm_start_stop_filter(char start_stop,
+				uint32_t reg, uint32_t addr)
+{
+	ptm.cfg.addr_comp_value[reg] = addr;
+
+	if (start_stop == 's')
+		ptm.cfg.te_start_stop_control |= (1 << reg);
+	else if (start_stop == 't')
+		ptm.cfg.te_start_stop_control |= (1 << (reg + 16));
+
+	ptm.cfg.te_control |= BIT(25);
+}
+
+#define MAX_COMMAND_STRLEN  40
+static ssize_t ptm_write(struct file *file, const char __user *data,
+				size_t len, loff_t *ppos)
+{
+	char command[MAX_COMMAND_STRLEN];
+	int str_len;
+	unsigned long reg1, reg2;
+	unsigned long addr1, addr2;
+
+	str_len = strnlen_user(data, MAX_COMMAND_STRLEN);
+	dev_dbg(ptm.dev, "string length: %d", str_len);
+	if (str_len == 0 || str_len == (MAX_COMMAND_STRLEN+1)) {
+		dev_err(ptm.dev, "error in str_len: %d", str_len);
+		return -EFAULT;
+	}
+	/* includes the null character */
+	if (copy_from_user(command, data, str_len)) {
+		dev_err(ptm.dev, "error in copy_from_user: %d", str_len);
+		return -EFAULT;
+	}
+
+	dev_dbg(ptm.dev, "input = %s", command);
+
+	switch (command[0]) {
+	case '0':
+		if (ptm.trace_enabled) {
+			ptm_trace_disable();
+			dev_info(ptm.dev, "tracing disabled\n");
+		} else
+			dev_err(ptm.dev, "trace already disabled\n");
+
+		break;
+	case '1':
+		if (!ptm.trace_enabled) {
+			if (!ptm_trace_enable())
+				dev_info(ptm.dev, "tracing enabled\n");
+			else
+				dev_err(ptm.dev, "error enabling trace\n");
+		} else
+			dev_err(ptm.dev, "trace already enabled\n");
+		break;
+	case 'f':
+		switch (command[2]) {
+		case 'i':
+			switch (command[4]) {
+			case 'i':
+				if (sscanf(&command[6], "%lx:%lx:%lx:%lx\\0",
+					&reg1, &addr1, &reg2, &addr2) != 4)
+					goto err_out;
+				if (reg1 > 7 || reg2 > 7 || (reg1 % 2))
+					goto err_out;
+				ptm_range_filter('i',
+						reg1, addr1, reg2, addr2);
+				break;
+			case 'e':
+				if (sscanf(&command[6], "%lx:%lx:%lx:%lx\\0",
+					&reg1, &addr1, &reg2, &addr2) != 4)
+					goto err_out;
+				if (reg1 > 7 || reg2 > 7 || (reg1 % 2)
+					|| command[2] == 'd')
+					goto err_out;
+				ptm_range_filter('e',
+						reg1, addr1, reg2, addr2);
+				break;
+			case 's':
+				if (sscanf(&command[6], "%lx:%lx\\0",
+					&reg1, &addr1) != 2)
+					goto err_out;
+				if (reg1 > 7)
+					goto err_out;
+				ptm_start_stop_filter('s', reg1, addr1);
+				break;
+			case 't':
+				if (sscanf(&command[6], "%lx:%lx\\0",
+						&reg1, &addr1) != 2)
+					goto err_out;
+				if (reg1 > 7)
+					goto err_out;
+				ptm_start_stop_filter('t', reg1, addr1);
+				break;
+			default:
+				goto err_out;
+			}
+			break;
+		case 'r':
+			ptm_cfg_rw_init();
+			break;
+		default:
+			goto err_out;
+		}
+		break;
+	default:
+		goto err_out;
+	}
+
+	return len;
+
+err_out:
+	return -EFAULT;
+}
+
+static int ptm_release(struct inode *inode, struct file *file)
+{
+	atomic_set(&ptm.in_use, 0);
+	dev_dbg(ptm.dev, "%s: released\n", __func__);
+	return 0;
+}
+
+static const struct file_operations ptm_fops = {
+	.owner =	THIS_MODULE,
+	.open =		ptm_open,
+	.write =	ptm_write,
+	.release =	ptm_release,
+};
+
+static struct miscdevice ptm_misc = {
+	.name =		"msm_ptm",
+	.minor =	MISC_DYNAMIC_MINOR,
+	.fops =		&ptm_fops,
+};
+
+static void ptm_save_reg(int cpu)
+{
+	uint32_t i;
+	int j;
+
+	PTM_UNLOCK(cpu);
+
+	i = cpu * MAX_TRACE_REGS;
+
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMCR);
+	ptm_set_prog(cpu);
+
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMTRIGGER);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMTSSCR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMTEEVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMTECR1);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMFFLR);
+	for (j = 0; j < ptm.cfg.nr_addr_comp; j++) {
+		ptm.state[i++] = ptm_readl(ptm, cpu, ETMACVRn(j));
+		ptm.state[i++] = ptm_readl(ptm, cpu, ETMACTRn(j));
+	}
+	for (j = 0; j < ptm.cfg.nr_cntr; j++) {
+		ptm.state[i++] = ptm_readl(ptm, cpu, ETMCNTRLDVRn(j));
+		ptm.state[i++] = ptm_readl(ptm, cpu, ETMCNTENRn(j));
+		ptm.state[i++] = ptm_readl(ptm, cpu, ETMCNTRLDEVRn(j));
+		ptm.state[i++] = ptm_readl(ptm, cpu, ETMCNTVRn(j));
+	}
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSQ12EVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSQ21EVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSQ23EVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSQ32EVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSQ13EVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSQ31EVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSQR);
+	for (j = 0; j < ptm.cfg.nr_ext_output; j++)
+		ptm.state[i++] = ptm_readl(ptm, cpu, ETMEXTOUTEVRn(j));
+	for (j = 0; j < ptm.cfg.nr_context_id_comp; j++)
+		ptm.state[i++] = ptm_readl(ptm, cpu, ETMCIDCVRn(j));
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMCIDCMR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMSYNCFR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMEXTINSELR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMTSEVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMAUXCR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, ETMVMIDCVR);
+	ptm.state[i++] = ptm_readl(ptm, cpu, CS_CLAIMSET);
+	ptm.state[i++] = ptm_readl(ptm, cpu, CS_CLAIMCLR);
+
+	PTM_LOCK(cpu);
+}
+
+static void ptm_restore_reg(int cpu)
+{
+	uint32_t i;
+	int j;
+
+	ptm_os_unlock(NULL);
+	PTM_UNLOCK(cpu);
+
+	i = cpu * MAX_TRACE_REGS;
+
+	ptm_clear_powerdown(cpu);
+	ptm_set_prog(cpu);
+	/* Ensure prog bit doesn't get cleared since we have set it above.
+	 * Power down bit should already be clear in the saved state.
+	 */
+	ptm_writel(ptm, cpu, ptm.state[i++] | BIT(10), ETMCR);
+
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMTRIGGER);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMTSSCR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMTEEVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMTECR1);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMFFLR);
+	for (j = 0; j < ptm.cfg.nr_addr_comp; j++) {
+		ptm_writel(ptm, cpu, ptm.state[i++], ETMACVRn(j));
+		ptm_writel(ptm, cpu, ptm.state[i++], ETMACTRn(j));
+	}
+	for (j = 0; j < ptm.cfg.nr_cntr; j++) {
+		ptm_writel(ptm, cpu, ptm.state[i++], ETMCNTRLDVRn(j));
+		ptm_writel(ptm, cpu, ptm.state[i++], ETMCNTENRn(j));
+		ptm_writel(ptm, cpu, ptm.state[i++], ETMCNTRLDEVRn(j));
+		ptm_writel(ptm, cpu, ptm.state[i++], ETMCNTVRn(j));
+	}
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSQ12EVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSQ21EVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSQ23EVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSQ32EVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSQ13EVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSQ31EVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSQR);
+	for (j = 0; j < ptm.cfg.nr_ext_output; j++)
+		ptm_writel(ptm, cpu, ptm.state[i++], ETMEXTOUTEVRn(j));
+	for (j = 0; j < ptm.cfg.nr_context_id_comp; j++)
+		ptm_writel(ptm, cpu, ptm.state[i++], ETMCIDCVRn(j));
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMCIDCMR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMSYNCFR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMEXTINSELR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMTSEVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMAUXCR);
+	ptm_writel(ptm, cpu, ptm.state[i++], ETMVMIDCVR);
+	ptm_writel(ptm, cpu, ptm.state[i++], CS_CLAIMSET);
+	ptm_writel(ptm, cpu, ptm.state[i++], CS_CLAIMCLR);
+
+	ptm_clear_prog(cpu);
+
+	PTM_LOCK(cpu);
+}
+
+/* etm_save_reg_check and etm_restore_reg_check should be fast
+ *
+ * These functions will be called either from:
+ * 1. per_cpu idle thread context for idle power collapses.
+ * 2. per_cpu idle thread context for hotplug/suspend power collapse for
+ *    nonboot cpus.
+ * 3. suspend thread context for core0.
+ *
+ * In all cases we are guaranteed to be running on the same cpu for the
+ * entire duration.
+ *
+ * Another assumption is that etm registers won't change after trace_enabled
+ * is set. Current usage model guarantees this doesn't happen.
+ */
+void etm_save_reg_check(void)
+{
+	/* Disabling all kinds of power_collapses when enabling and disabling
+	 * trace provides mutual exclusion to be able to safely access
+	 * ptm.trace_enabled here.
+	 */
+	if (ptm.trace_enabled) {
+		int cpu = smp_processor_id();
+
+		/* Don't save the registers if we just got called from per_cpu
+		 * idle thread context of a nonboot cpu after hotplug/suspend
+		 * power collapse. This is to prevent corruption due to saving
+		 * twice since nonboot cpus start out fresh without the
+		 * corresponding restore.
+		 */
+		if (!(*per_cpu_ptr(ptm.cpu_restore, cpu))) {
+			ptm_save_reg(cpu);
+			*per_cpu_ptr(ptm.cpu_restore, cpu) = 1;
+		}
+	}
+}
+
+void etm_restore_reg_check(void)
+{
+	/* Disabling all kinds of power_collapses when enabling and disabling
+	 * trace provides mutual exclusion to be able to safely access
+	 * ptm.trace_enabled here.
+	 */
+	if (ptm.trace_enabled) {
+		int cpu = smp_processor_id();
+
+		ptm_restore_reg(cpu);
+		*per_cpu_ptr(ptm.cpu_restore, cpu) = 0;
+	}
+}
+
+static void ptm_cfg_rw_init(void)
+{
+	int i;
+
+	ptm.cfg.main_control =				0x00001000;
+	ptm.cfg.trigger_event =				0x0000406F;
+	ptm.cfg.te_start_stop_control =			0x00000000;
+	ptm.cfg.te_event =				0x0000006F;
+	ptm.cfg.te_control =				0x01000000;
+	ptm.cfg.fifofull_level =			0x00000028;
+	for (i = 0; i < ptm.cfg.nr_addr_comp; i++) {
+		ptm.cfg.addr_comp_value[i] =		0x00000000;
+		ptm.cfg.addr_comp_access_type[i] =	0x00000000;
+	}
+	for (i = 0; i < ptm.cfg.nr_cntr; i++) {
+		ptm.cfg.cntr_reload_value[i] =		0x00000000;
+		ptm.cfg.cntr_enable_event[i] =		0x0000406F;
+		ptm.cfg.cntr_reload_event[i] =		0x0000406F;
+		ptm.cfg.cntr_value[i] =			0x00000000;
+	}
+	ptm.cfg.seq_state_12_event =			0x0000406F;
+	ptm.cfg.seq_state_21_event =			0x0000406F;
+	ptm.cfg.seq_state_23_event =			0x0000406F;
+	ptm.cfg.seq_state_32_event =			0x0000406F;
+	ptm.cfg.seq_state_13_event =			0x0000406F;
+	ptm.cfg.seq_state_31_event =			0x0000406F;
+	ptm.cfg.current_seq_state =			0x00000000;
+	for (i = 0; i < ptm.cfg.nr_ext_output; i++)
+		ptm.cfg.ext_output_event[i] =		0x0000406F;
+	for (i = 0; i < ptm.cfg.nr_context_id_comp; i++)
+		ptm.cfg.context_id_comp_value[i] =	0x00000000;
+	ptm.cfg.context_id_comp_mask =			0x00000000;
+	ptm.cfg.sync_freq =				0x00000080;
+	ptm.cfg.extnd_ext_input_sel =			0x00000000;
+	ptm.cfg.ts_event =				0x0000406F;
+	ptm.cfg.aux_control =				0x00000000;
+	ptm.cfg.vmid_comp_value =			0x00000000;
+}
+
+static void ptm_cfg_ro_init(void)
+{
+	/* use cpu 0 for setup */
+	int cpu = 0;
+
+	ptm_os_unlock(NULL);
+	smp_call_function(ptm_os_unlock, NULL, 1);
+	PTM_UNLOCK(cpu);
+	ptm_clear_powerdown(cpu);
+	ptm_set_prog(cpu);
+
+	/* find all capabilities */
+	ptm.cfg.config_code	=	ptm_readl(ptm, cpu, ETMCCR);
+	ptm.cfg.nr_addr_comp =		BMVAL(ptm.cfg.config_code, 0, 3) * 2;
+	ptm.cfg.nr_cntr =		BMVAL(ptm.cfg.config_code, 13, 15);
+	ptm.cfg.nr_ext_input =		BMVAL(ptm.cfg.config_code, 17, 19);
+	ptm.cfg.nr_ext_output =		BMVAL(ptm.cfg.config_code, 20, 22);
+	ptm.cfg.nr_context_id_comp =	BMVAL(ptm.cfg.config_code, 24, 25);
+
+	ptm.cfg.config_code_extn =	ptm_readl(ptm, cpu, ETMCCER);
+	ptm.cfg.nr_extnd_ext_input_sel =
+					BMVAL(ptm.cfg.config_code_extn, 0, 2);
+	ptm.cfg.nr_instr_resources =	BMVAL(ptm.cfg.config_code_extn, 13, 15);
+
+	ptm.cfg.system_config =		ptm_readl(ptm, cpu, ETMSCR);
+	ptm.cfg.fifofull_supported =	BVAL(ptm.cfg.system_config, 8);
+	ptm.cfg.nr_procs_supported =	BMVAL(ptm.cfg.system_config, 12, 14);
+
+	ptm_set_powerdown(cpu);
+	PTM_LOCK(cpu);
+}
+
+static int __devinit ptm_probe(struct platform_device *pdev)
+{
+	int ret, cpu;
+	struct resource *res;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		ret = -EINVAL;
+		goto err_res;
+	}
+
+	ptm.base = ioremap_nocache(res->start, resource_size(res));
+	if (!ptm.base) {
+		ret = -EINVAL;
+		goto err_ioremap;
+	}
+
+	ptm.dev = &pdev->dev;
+
+	ptm.state = kzalloc(MAX_STATE_SIZE * sizeof(uint32_t), GFP_KERNEL);
+	if (!ptm.state) {
+		ret = -ENOMEM;
+		goto err_kzalloc;
+	}
+
+	ret = misc_register(&ptm_misc);
+	if (ret)
+		goto err_misc;
+
+	ptm.qdss_at_clk = clk_get(NULL, "qdss_at_clk");
+	if (IS_ERR(ptm.qdss_at_clk)) {
+		ret = PTR_ERR(ptm.qdss_at_clk);
+		goto err_at;
+	}
+	ret = clk_set_rate(ptm.qdss_at_clk, 300000000);
+	if (ret)
+		goto err_at_rate;
+	ret = clk_enable(ptm.qdss_at_clk);
+	if (ret)
+		goto err_at_enable;
+
+	ptm.qdss_pclkdbg_clk = clk_get(NULL, "qdss_pclkdbg_clk");
+	if (IS_ERR(ptm.qdss_pclkdbg_clk)) {
+		ret = PTR_ERR(ptm.qdss_pclkdbg_clk);
+		goto err_pclkdbg;
+	}
+	ret = clk_enable(ptm.qdss_pclkdbg_clk);
+	if (ret)
+		goto err_pclkdbg_enable;
+
+	ptm.qdss_pclk = clk_get(NULL, "qdss_pclk");
+	if (IS_ERR(ptm.qdss_pclk)) {
+		ret = PTR_ERR(ptm.qdss_pclk);
+		goto err_pclk;
+	}
+
+	ret = clk_enable(ptm.qdss_pclk);
+	if (ret)
+		goto err_pclk_enable;
+
+	ptm.qdss_traceclkin_clk = clk_get(NULL, "qdss_traceclkin_clk");
+	if (IS_ERR(ptm.qdss_traceclkin_clk)) {
+		ret = PTR_ERR(ptm.qdss_traceclkin_clk);
+		goto err_traceclkin;
+	}
+	ret = clk_set_rate(ptm.qdss_traceclkin_clk, 300000000);
+	if (ret)
+		goto err_traceclkin_rate;
+	ret = clk_enable(ptm.qdss_traceclkin_clk);
+	if (ret)
+		goto err_traceclkin_enable;
+
+	ptm.qdss_tsctr_clk = clk_get(NULL, "qdss_tsctr_clk");
+	if (IS_ERR(ptm.qdss_tsctr_clk)) {
+		ret = PTR_ERR(ptm.qdss_tsctr_clk);
+		goto err_tsctr;
+	}
+	ret = clk_set_rate(ptm.qdss_tsctr_clk, 400000000);
+	if (ret)
+		goto err_tsctr_rate;
+
+	ret = clk_enable(ptm.qdss_tsctr_clk);
+	if (ret)
+		goto err_tsctr_enable;
+
+	ptm_cfg_ro_init();
+	ptm_cfg_rw_init();
+
+	ptm.trace_enabled = false;
+
+	ptm.cpu_restore = alloc_percpu(int);
+	if (!ptm.cpu_restore) {
+		ret = -ENOMEM;
+		goto err_percpu;
+	}
+
+	for_each_possible_cpu(cpu)
+		*per_cpu_ptr(ptm.cpu_restore, cpu) = 0;
+
+	wake_lock_init(&ptm.wake_lock, WAKE_LOCK_SUSPEND, "msm_ptm");
+	pm_qos_add_request(&ptm.qos_req, PM_QOS_CPU_DMA_LATENCY,
+						PM_QOS_DEFAULT_VALUE);
+	atomic_set(&ptm.in_use, 0);
+
+	clk_disable(ptm.qdss_tsctr_clk);
+	clk_disable(ptm.qdss_traceclkin_clk);
+	clk_disable(ptm.qdss_pclk);
+	clk_disable(ptm.qdss_pclkdbg_clk);
+	clk_disable(ptm.qdss_at_clk);
+
+	dev_info(ptm.dev, "PTM intialized.\n");
+
+	if (trace_on_boot) {
+		if (!ptm_trace_enable())
+			dev_info(ptm.dev, "tracing enabled\n");
+		else
+			dev_err(ptm.dev, "error enabling trace\n");
+	}
+
+	return 0;
+
+err_percpu:
+	clk_disable(ptm.qdss_tsctr_clk);
+err_tsctr_enable:
+err_tsctr_rate:
+	clk_put(ptm.qdss_tsctr_clk);
+err_tsctr:
+	clk_disable(ptm.qdss_traceclkin_clk);
+err_traceclkin_enable:
+err_traceclkin_rate:
+	clk_put(ptm.qdss_traceclkin_clk);
+err_traceclkin:
+	clk_disable(ptm.qdss_pclk);
+err_pclk_enable:
+	clk_put(ptm.qdss_pclk);
+err_pclk:
+	clk_disable(ptm.qdss_pclkdbg_clk);
+err_pclkdbg_enable:
+	clk_put(ptm.qdss_pclkdbg_clk);
+err_pclkdbg:
+	clk_disable(ptm.qdss_at_clk);
+err_at_enable:
+err_at_rate:
+	clk_put(ptm.qdss_at_clk);
+err_at:
+	misc_deregister(&ptm_misc);
+err_misc:
+	kfree(ptm.state);
+err_kzalloc:
+	iounmap(ptm.base);
+err_ioremap:
+err_res:
+	return ret;
+}
+
+static int __devexit ptm_remove(struct platform_device *pdev)
+{
+	if (ptm.trace_enabled)
+		ptm_trace_disable();
+	pm_qos_remove_request(&ptm.qos_req);
+	wake_lock_destroy(&ptm.wake_lock);
+	free_percpu(ptm.cpu_restore);
+	clk_put(ptm.qdss_tsctr_clk);
+	clk_put(ptm.qdss_traceclkin_clk);
+	clk_put(ptm.qdss_pclk);
+	clk_put(ptm.qdss_pclkdbg_clk);
+	clk_put(ptm.qdss_at_clk);
+	misc_deregister(&ptm_misc);
+	kfree(ptm.state);
+	iounmap(ptm.base);
+
+	return 0;
+}
+
+static struct platform_driver ptm_driver = {
+	.probe          = ptm_probe,
+	.remove         = __devexit_p(ptm_remove),
+	.driver         = {
+		.name   = "msm_ptm",
+	},
+};
+
+static int __init ptm_init(void)
+{
+	return platform_driver_register(&ptm_driver);
+}
+module_init(ptm_init);
+
+static void __exit ptm_exit(void)
+{
+	platform_driver_unregister(&ptm_driver);
+}
+module_exit(ptm_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Coresight Program Flow Trace driver");