gsi: Add clock voting before IO access in debugfs

The debugfs functions may be called while the GSI is not clocked.
This will lead to kernel panic due to bus error.
Fixing by clock voting before IO access and unvoting after.

Change-Id: I99b1f69df9be5774d688029886b1aef8dfacc657
Signed-off-by: Ilia Lin <[email protected]>

drivers/platform/msm/gsi/gsi.h

@@ -328,6 +328,8 @@ struct gsi_per_props {
 	void *user_data;
 	int (*clk_status_cb)(void);
 	void (*enable_clk_bug_on)(void);
+	void (*vote_clk_cb)(void);
+	void (*unvote_clk_cb)(void);
 	bool skip_ieob_mask_wa;
 	bool tx_poll;
 };

drivers/platform/msm/gsi/gsi_dbg.c

@@ -71,6 +71,8 @@ static ssize_t gsi_dump_evt(struct file *file,
 		return -EINVAL;
 	}
 
+	gsi_ctx->per.vote_clk_cb();
+
 	val = gsihal_read_reg_nk(GSI_EE_n_EV_CH_k_CNTXT_0,
 		gsi_ctx->per.ee, arg1);
 	TERR("EV%2d CTX0  0x%x\n", arg1, val);
@@ -120,6 +122,8 @@ static ssize_t gsi_dump_evt(struct file *file,
 		gsi_ctx->per.ee, arg1);
 	TERR("EV%2d SCR1  0x%x\n", arg1, val);
 
+	gsi_ctx->per.unvote_clk_cb();
+
 	if (arg2) {
 		ctx = &gsi_ctx->evtr[arg1];
 
@@ -183,7 +187,9 @@ static ssize_t gsi_dump_ch(struct file *file,
 		return -EINVAL;
 	}
 
+	gsi_ctx->per.vote_clk_cb();
 	gsi_dump_ch_info(arg1);
+	gsi_ctx->per.unvote_clk_cb();
 
 	if (arg2) {
 		ctx = &gsi_ctx->chan[arg1];
@@ -354,7 +360,6 @@ static ssize_t gsi_set_max_elem_dp_stats(struct file *file,
 	unsigned long missing;
 	char *sptr, *token;
 
-
 	if (count >= sizeof(dbg_buff))
 		goto error;
 
@@ -432,6 +437,8 @@ static void gsi_dbg_update_ch_dp_stats(struct gsi_chan_ctx *ctx)
 	int ee = gsi_ctx->per.ee;
 	uint16_t used_hw;
 
+	gsi_ctx->per.vote_clk_cb();
+
 	rp_hw = gsihal_read_reg_nk(GSI_EE_n_GSI_CH_k_CNTXT_4,
 		ee, ctx->props.ch_id);
 	rp_hw |= ((uint64_t)gsihal_read_reg_nk(GSI_EE_n_GSI_CH_k_CNTXT_5,
@@ -442,6 +449,8 @@ static void gsi_dbg_update_ch_dp_stats(struct gsi_chan_ctx *ctx)
 	wp_hw |= ((uint64_t)gsihal_read_reg_nk(GSI_EE_n_GSI_CH_k_CNTXT_7,
 		ee, ctx->props.ch_id)) << 32;
 
+	gsi_ctx->per.unvote_clk_cb();
+
 	start_hw = gsi_find_idx_from_addr(&ctx->ring, rp_hw);
 	end_hw = gsi_find_idx_from_addr(&ctx->ring, wp_hw);
 
@@ -590,7 +599,7 @@ static ssize_t gsi_read_gsi_hw_profiling_stats(struct file *file,
 	char __user *buf, size_t count, loff_t *ppos)
 {
 	struct gsi_hw_profiling_data stats;
-	int nbytes, cnt = 0;
+	int ret, nbytes, cnt = 0;
 	u64 totalCycles = 0, util = 0;
 
 	if (gsi_ctx->per.ver < GSI_VER_2_9) {
@@ -599,7 +608,12 @@ static ssize_t gsi_read_gsi_hw_profiling_stats(struct file *file,
 		cnt += nbytes;
 		goto done;
 	}
-	if (!gsi_get_hw_profiling_stats(&stats)) {
+
+	gsi_ctx->per.vote_clk_cb();
+	ret = gsi_get_hw_profiling_stats(&stats);
+	gsi_ctx->per.unvote_clk_cb();
+
+	if (!ret) {
 		totalCycles = stats.mcs_busy_cnt + stats.mcs_idle_cnt +
 			stats.bp_and_pending_cnt;
 		if (totalCycles != 0)
@@ -636,7 +650,7 @@ static ssize_t gsi_read_gsi_fw_version(struct file *file,
 	char __user *buf, size_t count, loff_t *ppos)
 {
 	struct gsi_fw_version ver;
-	int nbytes, cnt = 0;
+	int ret, nbytes, cnt = 0;
 
 	if (gsi_ctx->per.ver < GSI_VER_2_9) {
 		nbytes = scnprintf(dbg_buff, GSI_MAX_MSG_LEN,
@@ -644,7 +658,12 @@ static ssize_t gsi_read_gsi_fw_version(struct file *file,
 		cnt += nbytes;
 		goto done;
 	}
-	if (!gsi_get_fw_version(&ver)) {
+
+	gsi_ctx->per.vote_clk_cb();
+	ret = gsi_get_fw_version(&ver);
+	gsi_ctx->per.unvote_clk_cb();
+
+	if (!ret) {
 		nbytes = scnprintf(dbg_buff, GSI_MAX_MSG_LEN,
 			"hw=%d\nflavor=%d\nfw=%d\n",
 			ver.hw,

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

@@ -6924,17 +6924,16 @@ void ipa3_active_clients_log_inc(struct ipa_active_client_logging_info *id,
 }
 
 /**
- * ipa3_inc_client_enable_clks() - Increase active clients counter, and
+ * ipa3_inc_client_enable_clks_no_log() - Increase active clients counter, and
  * enable ipa clocks if necessary
  *
  * Return codes:
  * None
  */
-void ipa3_inc_client_enable_clks(struct ipa_active_client_logging_info *id)
+static void ipa3_inc_client_enable_clks_no_log(void)
 {
 	int ret;
 
-	ipa3_active_clients_log_inc(id, false);
 	ret = atomic_inc_not_zero(&ipa3_ctx->ipa3_active_clients.cnt);
 	if (ret) {
 		IPADBG_LOW("active clients = %d\n",
@@ -6960,6 +6959,19 @@ void ipa3_inc_client_enable_clks(struct ipa_active_client_logging_info *id)
 		atomic_read(&ipa3_ctx->ipa3_active_clients.cnt));
 	mutex_unlock(&ipa3_ctx->ipa3_active_clients.mutex);
 }
+
+/**
+ * ipa3_inc_client_enable_clks() - Increase active clients counter and
+ * enable ipa clocks if necessary, log the caller
+ *
+ * Return codes:
+ * None
+ */
+void ipa3_inc_client_enable_clks(struct ipa_active_client_logging_info *id)
+{
+	ipa3_active_clients_log_inc(id, false);
+	ipa3_inc_client_enable_clks_no_log();
+}
 EXPORT_SYMBOL(ipa3_inc_client_enable_clks);
 
 static void ipa3_handle_gsi_differ_irq(void)
@@ -7064,7 +7076,23 @@ bail:
 }
 
 /**
- * ipa3_dec_client_disable_clks() - Decrease active clients counter
+ * ipa3_dec_client_disable_clks_no_log() - Decrease active clients counter
+ *
+ * In case that there are no active clients this function also starts
+ * TAG process. When TAG progress ends ipa clocks will be gated.
+ * start_tag_process_again flag is set during this function to signal TAG
+ * process to start again as there was another client that may send data to ipa
+ *
+ * Return codes:
+ * None
+ */
+static void ipa3_dec_client_disable_clks_no_log(void)
+{
+	__ipa3_dec_client_disable_clks();
+}
+
+/**
+ * ipa3_dec_client_disable_clks() - Decrease active clients counter and log caller
  *
  * In case that there are no active clients this function also starts
  * TAG process. When TAG progress ends ipa clocks will be gated.
@@ -8102,6 +8130,8 @@ static int ipa3_post_init(const struct ipa3_plat_drv_res *resource_p,
 	gsi_props.rel_clk_cb = NULL;
 	gsi_props.clk_status_cb = ipa3_active_clks_status;
 	gsi_props.enable_clk_bug_on = ipa3_handle_gsi_differ_irq;
+	gsi_props.vote_clk_cb = ipa3_inc_client_enable_clks_no_log;
+	gsi_props.unvote_clk_cb = ipa3_dec_client_disable_clks_no_log;
 
 	if (ipa3_ctx->ipa_config_is_mhi) {
 		gsi_props.mhi_er_id_limits_valid = true;