msm: ipa3: allocate ipa_low IPC only when needed

for data path and other frequent log prints, IPA driver is
using a debugfs trigger to enable those.
This change is an optimization to allocate IPC resources only
when needed instead of on boot up.

CRs-Fixed: 1005492
Change-Id: I6e7ac15ea7256c18e4174de56adb532ab6c6b0d0
Acked-by: Ady Abraham <adya@qti.qualcomm.com>
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>

drivers/platform/msm/ipa/ipa_api.c

@@ -2503,6 +2503,32 @@ int ipa_set_required_perf_profile(enum ipa_voltage_level floor_voltage,
 }
 EXPORT_SYMBOL(ipa_set_required_perf_profile);
 
+/**
+ * ipa_get_ipc_logbuf() - return a pointer to IPA driver IPC log
+ */
+void *ipa_get_ipc_logbuf(void)
+{
+	void *ret;
+
+	IPA_API_DISPATCH_RETURN_PTR(ipa_get_ipc_logbuf);
+
+	return ret;
+}
+EXPORT_SYMBOL(ipa_get_ipc_logbuf);
+
+/**
+ * ipa_get_ipc_logbuf_low() - return a pointer to IPA driver IPC low prio log
+ */
+void *ipa_get_ipc_logbuf_low(void)
+{
+	void *ret;
+
+	IPA_API_DISPATCH_RETURN_PTR(ipa_get_ipc_logbuf_low);
+
+	return ret;
+}
+EXPORT_SYMBOL(ipa_get_ipc_logbuf_low);
+
 static const struct dev_pm_ops ipa_pm_ops = {
 	.suspend_noirq = ipa_ap_suspend,
 	.resume_noirq = ipa_ap_resume,

drivers/platform/msm/ipa/ipa_api.h

@@ -303,6 +303,10 @@ struct ipa_api_controller {
 	int (*ipa_set_required_perf_profile)(
 		enum ipa_voltage_level floor_voltage, u32 bandwidth_mbps);
 
+	void *(*ipa_get_ipc_logbuf)(void);
+
+	void *(*ipa_get_ipc_logbuf_low)(void);
+
 };
 
 #ifdef CONFIG_IPA

drivers/platform/msm/ipa/ipa_common_i.h

@@ -12,6 +12,7 @@
 
 #ifndef _IPA_COMMON_I_H_
 #define _IPA_COMMON_I_H_
+#include <linux/ipc_logging.h>
 
 #define __FILENAME__ \
 	(strrchr(__FILE__, '/') ? strrchr(__FILE__, '/') + 1 : __FILE__)
@@ -114,6 +115,13 @@ struct ipa_active_client_logging_info {
 
 extern const char *ipa_clients_strings[];
 
+#define IPA_IPC_LOGGING(buf, fmt, args...) \
+	do { \
+		if (buf) \
+			ipc_log_string((buf), fmt, __func__, __LINE__, \
+				## args); \
+	} while (0)
+
 void ipa_inc_client_enable_clks(struct ipa_active_client_logging_info *id);
 void ipa_dec_client_disable_clks(struct ipa_active_client_logging_info *id);
 int ipa_inc_client_enable_clks_no_block(
@@ -123,6 +131,8 @@ int ipa_resume_resource(enum ipa_rm_resource_name name);
 int ipa_suspend_resource_sync(enum ipa_rm_resource_name resource);
 int ipa_set_required_perf_profile(enum ipa_voltage_level floor_voltage,
 	u32 bandwidth_mbps);
+void *ipa_get_ipc_logbuf(void);
+void *ipa_get_ipc_logbuf_low(void);
 
 
 #endif /* _IPA_COMMON_I_H_ */

drivers/platform/msm/ipa/ipa_v3/ipa.c

@@ -67,8 +67,6 @@
 
 #define IPA_TRANSPORT_PROD_TIMEOUT_MSEC 100
 
-#define IPA_IPC_LOG_PAGES 50
-
 #define IPA3_ACTIVE_CLIENTS_TABLE_BUF_SIZE 2048
 
 #define IPA3_ACTIVE_CLIENT_LOG_TYPE_EP 0
@@ -3958,13 +3956,6 @@ static int ipa3_pre_init(const struct ipa3_plat_drv_res *resource_p,
 		result = -ENOMEM;
 		goto fail_logbuf;
 	}
-	ipa3_ctx->logbuf_low =
-		ipc_log_context_create(IPA_IPC_LOG_PAGES, "ipa_low", 0);
-	if (ipa3_ctx->logbuf_low == NULL) {
-		IPAERR("failed to get logbuf_low\n");
-		result = -ENOMEM;
-		goto fail_logbuf_low;
-	}
 
 	ipa3_ctx->pdev = ipa_dev;
 	ipa3_ctx->uc_pdev = ipa_dev;
@@ -4460,8 +4451,6 @@ fail_bus_reg:
 fail_bind:
 	kfree(ipa3_ctx->ctrl);
 fail_mem_ctrl:
-	ipc_log_context_destroy(ipa3_ctx->logbuf_low);
-fail_logbuf_low:
 	ipc_log_context_destroy(ipa3_ctx->logbuf);
 fail_logbuf:
 	kfree(ipa3_ctx);

drivers/platform/msm/ipa/ipa_v3/ipa_debugfs.c

@@ -1587,6 +1587,43 @@ static ssize_t ipa3_clear_active_clients_log(struct file *file,
 	return count;
 }
 
+static ssize_t ipa3_enable_ipc_low(struct file *file,
+	const char __user *ubuf, size_t count, loff_t *ppos)
+{
+	unsigned long missing;
+	s8 option = 0;
+
+	if (sizeof(dbg_buff) < count + 1)
+		return -EFAULT;
+
+	missing = copy_from_user(dbg_buff, ubuf, count);
+	if (missing)
+		return -EFAULT;
+
+	dbg_buff[count] = '\0';
+	if (kstrtos8(dbg_buff, 0, &option))
+		return -EFAULT;
+
+	if (option) {
+		if (!ipa3_ctx->logbuf_low) {
+			ipa3_ctx->logbuf_low =
+				ipc_log_context_create(IPA_IPC_LOG_PAGES,
+					"ipa_low", 0);
+		}
+
+		if (ipa3_ctx->logbuf_low == NULL) {
+			IPAERR("failed to get logbuf_low\n");
+			return -EFAULT;
+		}
+	} else {
+		if (ipa3_ctx->logbuf_low)
+			ipc_log_context_destroy(ipa3_ctx->logbuf_low);
+		ipa3_ctx->logbuf_low = NULL;
+	}
+
+	return count;
+}
+
 const struct file_operations ipa3_gen_reg_ops = {
 	.read = ipa3_read_gen_reg,
 };
@@ -1671,6 +1708,10 @@ const struct file_operations ipa3_active_clients = {
 	.write = ipa3_clear_active_clients_log,
 };
 
+const struct file_operations ipa3_ipc_low_ops = {
+	.write = ipa3_enable_ipc_low,
+};
+
 void ipa3_debugfs_init(void)
 {
 	const mode_t read_only_mode = S_IRUSR | S_IRGRP | S_IROTH;
@@ -1883,8 +1924,8 @@ void ipa3_debugfs_init(void)
 		goto fail;
 	}
 
-	file = debugfs_create_u32("enable_low_prio_print", read_write_mode,
+	file = debugfs_create_file("enable_low_prio_print", write_only_mode,
-		dent, &ipa3_ctx->enable_low_prio_print);
+		dent, 0, &ipa3_ipc_low_ops);
 	if (!file) {
 		IPAERR("could not create enable_low_prio_print file\n");
 		goto fail;

drivers/platform/msm/ipa/ipa_v3/ipa_i.h

@@ -56,32 +56,35 @@
 
 #define IPA_MAX_STATUS_STAT_NUM 30
 
-#define IPA_IPC_LOGGING(buf, fmt, args...) \
+#define IPA_IPC_LOG_PAGES 50
-	ipc_log_string((buf), \
-		DRV_NAME " %s:%d " fmt, __func__, __LINE__, ## args)
 
 #define IPADBG(fmt, args...) \
 	do { \
 		pr_debug(DRV_NAME " %s:%d " fmt, __func__, __LINE__, ## args);\
 		if (ipa3_ctx) { \
-			IPA_IPC_LOGGING(ipa3_ctx->logbuf, fmt, ## args); \
+			IPA_IPC_LOGGING(ipa3_ctx->logbuf, \
-			IPA_IPC_LOGGING(ipa3_ctx->logbuf_low, fmt, ## args); \
+				DRV_NAME " %s:%d " fmt, ## args); \
+			IPA_IPC_LOGGING(ipa3_ctx->logbuf_low, \
+				DRV_NAME " %s:%d " fmt, ## args); \
 		} \
 	} while (0)
 
 #define IPADBG_LOW(fmt, args...) \
 	do { \
 		pr_debug(DRV_NAME " %s:%d " fmt, __func__, __LINE__, ## args);\
-		if (ipa3_ctx && ipa3_ctx->enable_low_prio_print) \
+		if (ipa3_ctx) \
-			IPA_IPC_LOGGING(ipa3_ctx->logbuf_low, fmt, ## args); \
+			IPA_IPC_LOGGING(ipa3_ctx->logbuf_low, \
+				DRV_NAME " %s:%d " fmt, ## args); \
 	} while (0)
 
 #define IPAERR(fmt, args...) \
 	do { \
 		pr_err(DRV_NAME " %s:%d " fmt, __func__, __LINE__, ## args);\
 		if (ipa3_ctx) { \
-			IPA_IPC_LOGGING(ipa3_ctx->logbuf, fmt, ## args); \
+			IPA_IPC_LOGGING(ipa3_ctx->logbuf, \
-			IPA_IPC_LOGGING(ipa3_ctx->logbuf_low, fmt, ## args); \
+				DRV_NAME " %s:%d " fmt, ## args); \
+			IPA_IPC_LOGGING(ipa3_ctx->logbuf_low, \
+				DRV_NAME " %s:%d " fmt, ## args); \
 		} \
 	} while (0)
 
@@ -1432,7 +1435,6 @@ struct ipa3_ready_cb_info {
  * @ctrl: holds the core specific operations based on
  *  core version (vtable like)
  * @enable_clock_scaling: clock scaling is enabled ?
- * @enable_low_prio_print: enable low priority prints
  * @curr_ipa_clk_rate: ipa3_clk current rate
  * @wcstats: wlan common buffer stats
  * @uc_ctx: uC interface context
@@ -1537,7 +1539,6 @@ struct ipa3_context {
 	struct device *uc_pdev;
 	spinlock_t idr_lock;
 	u32 enable_clock_scaling;
-	u32 enable_low_prio_print;
 	u32 curr_ipa_clk_rate;
 	bool q6_proxy_clk_vote_valid;
 	u32 ipa_num_pipes;