[PATCH 2/6] tty: serial: qcom_geni_serial: Add interconnect support

[Akash Asthana <akashast@xxxxxxxxxxxxxx>]

Get the interconnect paths for Uart based Serial Engine device
and vote according to the baud rate requirement of the driver.

Signed-off-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>
---
 drivers/tty/serial/qcom_geni_serial.c | 84 ++++++++++++++++++++++++++++++-----
 1 file changed, 74 insertions(+), 10 deletions(-)

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 191abb1..a8fb2b7 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -174,6 +174,35 @@ static struct qcom_geni_serial_port qcom_geni_console_port = {
 	},
 };
 
+static int geni_serial_icc_get(struct geni_se *se)
+{
+	if (!se)
+		return -EINVAL;
+
+	se->icc_path[GENI_TO_CORE] = of_icc_get(se->dev, "qup-core");
+	if (IS_ERR(se->icc_path[GENI_TO_CORE]))
+		return PTR_ERR(se->icc_path[GENI_TO_CORE]);
+
+	se->icc_path[CPU_TO_GENI] = of_icc_get(se->dev, "qup-config");
+	if (IS_ERR(se->icc_path[CPU_TO_GENI])) {
+		icc_put(se->icc_path[GENI_TO_CORE]);
+		se->icc_path[GENI_TO_CORE] = NULL;
+		return PTR_ERR(se->icc_path[CPU_TO_GENI]);
+	}
+
+	return 0;
+}
+
+void geni_serial_icc_put(struct geni_se *se)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(se->icc_path); i++) {
+		icc_put(se->icc_path[i]);
+		se->icc_path[i] = NULL;
+	}
+}
+
 static int qcom_geni_serial_request_port(struct uart_port *uport)
 {
 	struct platform_device *pdev = to_platform_device(uport->dev);
@@ -949,6 +978,12 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport,
 	ser_clk_cfg = SER_CLK_EN;
 	ser_clk_cfg |= clk_div << CLK_DIV_SHFT;
 
+	/* Put BW vote only on CPU path as driver supports FIFO mode only */
+	port->se.avg_bw_cpu = Bps_to_icc(baud);
+	port->se.peak_bw_cpu = Bps_to_icc(2 * baud);
+	icc_set_bw(port->se.icc_path[CPU_TO_GENI], port->se.avg_bw_cpu,
+			port->se.peak_bw_cpu);
+
 	/* parity */
 	tx_trans_cfg = readl(uport->membase + SE_UART_TX_TRANS_CFG);
 	tx_parity_cfg = readl(uport->membase + SE_UART_TX_PARITY_CFG);
@@ -1179,11 +1214,20 @@ static void qcom_geni_serial_pm(struct uart_port *uport,
 	if (old_state == UART_PM_STATE_UNDEFINED)
 		old_state = UART_PM_STATE_OFF;
 
-	if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF)
+	if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) {
+		/* Put BW vote for core clocks and CPU */
+		icc_set_bw(port->se.icc_path[GENI_TO_CORE],
+			port->se.avg_bw_core, port->se.peak_bw_core);
+		icc_set_bw(port->se.icc_path[CPU_TO_GENI], port->se.avg_bw_cpu,
+			port->se.peak_bw_cpu);
 		geni_se_resources_on(&port->se);
-	else if (new_state == UART_PM_STATE_OFF &&
-			old_state == UART_PM_STATE_ON)
+	} else if (new_state == UART_PM_STATE_OFF &&
+			old_state == UART_PM_STATE_ON) {
 		geni_se_resources_off(&port->se);
+		/* Remove BW vote from core clocks and CPU */
+		icc_set_bw(port->se.icc_path[GENI_TO_CORE], 0, 0);
+		icc_set_bw(port->se.icc_path[CPU_TO_GENI], 0, 0);
+	}
 }
 
 static const struct uart_ops qcom_geni_console_pops = {
@@ -1274,15 +1318,30 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
 	port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
 	port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
 
+	ret = geni_serial_icc_get(&port->se);
+	if (ret)
+		return ret;
+	/* Set the bus quota to a reasonable value */
+	port->se.avg_bw_core = console ? Bps_to_icc(1000) :
+		Bps_to_icc(CORE_2X_50_MHZ);
+	port->se.peak_bw_core = console ? Bps_to_icc(1000) :
+		Bps_to_icc(CORE_2X_100_MHZ);
+	port->se.avg_bw_cpu = Bps_to_icc(1000);
+	port->se.avg_bw_cpu = Bps_to_icc(1000);
+
 	port->name = devm_kasprintf(uport->dev, GFP_KERNEL,
 			"qcom_geni_serial_%s%d",
 			uart_console(uport) ? "console" : "uart", uport->line);
-	if (!port->name)
-		return -ENOMEM;
+	if (!port->name) {
+		ret = -ENOMEM;
+		goto geni_serial_put_icc;
+	}
 
 	irq = platform_get_irq(pdev, 0);
-	if (irq < 0)
-		return irq;
+	if (irq < 0) {
+		ret = irq;
+		goto geni_serial_put_icc;
+	}
 	uport->irq = irq;
 	uport->has_sysrq = IS_ENABLED(CONFIG_SERIAL_QCOM_GENI_CONSOLE);
 
@@ -1295,7 +1354,7 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
 
 	ret = uart_add_one_port(drv, uport);
 	if (ret)
-		return ret;
+		goto geni_serial_put_icc;
 
 	irq_set_status_flags(uport->irq, IRQ_NOAUTOEN);
 	ret = devm_request_irq(uport->dev, uport->irq, qcom_geni_serial_isr,
@@ -1303,7 +1362,7 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
 	if (ret) {
 		dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret);
 		uart_remove_one_port(drv, uport);
-		return ret;
+		goto geni_serial_put_icc;
 	}
 
 	/*
@@ -1320,11 +1379,15 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
 		if (ret) {
 			device_init_wakeup(&pdev->dev, false);
 			uart_remove_one_port(drv, uport);
-			return ret;
+			goto geni_serial_put_icc;
 		}
 	}
 
 	return 0;
+
+geni_serial_put_icc:
+	geni_serial_icc_put(&port->se);
+	return ret;
 }
 
 static int qcom_geni_serial_remove(struct platform_device *pdev)
@@ -1335,6 +1398,7 @@ static int qcom_geni_serial_remove(struct platform_device *pdev)
 	dev_pm_clear_wake_irq(&pdev->dev);
 	device_init_wakeup(&pdev->dev, false);
 	uart_remove_one_port(drv, &port->uport);
+	geni_serial_icc_put(&port->se);
 
 	return 0;
 }
-- 
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