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@@ -1,7 +1,7 @@
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/*
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* Xilinx PS UART driver
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*
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- * 2011 (c) Xilinx Inc.
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+ * 2011 - 2013 (C) Xilinx Inc.
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*
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* This program is free software; you can redistribute it
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* and/or modify it under the terms of the GNU General Public
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@@ -11,13 +11,17 @@
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*
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*/
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+#if defined(CONFIG_SERIAL_XILINX_PS_UART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
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+#define SUPPORT_SYSRQ
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+#endif
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+
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#include <linux/platform_device.h>
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#include <linux/serial.h>
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+#include <linux/console.h>
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#include <linux/serial_core.h>
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#include <linux/slab.h>
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#include <linux/tty.h>
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#include <linux/tty_flip.h>
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-#include <linux/console.h>
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#include <linux/clk.h>
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#include <linux/irq.h>
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#include <linux/io.h>
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@@ -29,12 +33,22 @@
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#define XUARTPS_MAJOR 0 /* use dynamic node allocation */
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#define XUARTPS_MINOR 0 /* works best with devtmpfs */
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#define XUARTPS_NR_PORTS 2
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-#define XUARTPS_FIFO_SIZE 16 /* FIFO size */
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+#define XUARTPS_FIFO_SIZE 64 /* FIFO size */
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#define XUARTPS_REGISTER_SPACE 0xFFF
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#define xuartps_readl(offset) ioread32(port->membase + offset)
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#define xuartps_writel(val, offset) iowrite32(val, port->membase + offset)
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+/* Rx Trigger level */
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+static int rx_trigger_level = 56;
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+module_param(rx_trigger_level, uint, S_IRUGO);
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+MODULE_PARM_DESC(rx_trigger_level, "Rx trigger level, 1-63 bytes");
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+
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+/* Rx Timeout */
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+static int rx_timeout = 10;
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+module_param(rx_timeout, uint, S_IRUGO);
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+MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
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+
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/********************************Register Map********************************/
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/** UART
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*
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@@ -128,6 +142,9 @@
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#define XUARTPS_IXR_RXEMPTY 0x00000002 /* RX FIFO empty interrupt. */
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#define XUARTPS_IXR_MASK 0x00001FFF /* Valid bit mask */
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+/* Goes in read_status_mask for break detection as the HW doesn't do it*/
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+#define XUARTPS_IXR_BRK 0x80000000
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+
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/** Channel Status Register
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*
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* The channel status register (CSR) is provided to enable the control logic
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@@ -139,15 +156,27 @@
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#define XUARTPS_SR_TXFULL 0x00000010 /* TX FIFO full */
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#define XUARTPS_SR_RXTRIG 0x00000001 /* Rx Trigger */
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+/* baud dividers min/max values */
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+#define XUARTPS_BDIV_MIN 4
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+#define XUARTPS_BDIV_MAX 255
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+#define XUARTPS_CD_MAX 65535
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+
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/**
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* struct xuartps - device data
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- * @refclk Reference clock
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- * @aperclk APB clock
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+ * @port Pointer to the UART port
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+ * @refclk Reference clock
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+ * @aperclk APB clock
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+ * @baud Current baud rate
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+ * @clk_rate_change_nb Notifier block for clock changes
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*/
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struct xuartps {
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+ struct uart_port *port;
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struct clk *refclk;
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struct clk *aperclk;
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+ unsigned int baud;
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+ struct notifier_block clk_rate_change_nb;
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};
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+#define to_xuartps(_nb) container_of(_nb, struct xuartps, clk_rate_change_nb);
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/**
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* xuartps_isr - Interrupt handler
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@@ -171,6 +200,23 @@ static irqreturn_t xuartps_isr(int irq, void *dev_id)
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*/
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isrstatus = xuartps_readl(XUARTPS_ISR_OFFSET);
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+ /*
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+ * There is no hardware break detection, so we interpret framing
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+ * error with all-zeros data as a break sequence. Most of the time,
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+ * there's another non-zero byte at the end of the sequence.
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+ */
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+
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+ if (isrstatus & XUARTPS_IXR_FRAMING) {
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+ while (!(xuartps_readl(XUARTPS_SR_OFFSET) &
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+ XUARTPS_SR_RXEMPTY)) {
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+ if (!xuartps_readl(XUARTPS_FIFO_OFFSET)) {
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+ port->read_status_mask |= XUARTPS_IXR_BRK;
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+ isrstatus &= ~XUARTPS_IXR_FRAMING;
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+ }
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+ }
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+ xuartps_writel(XUARTPS_IXR_FRAMING, XUARTPS_ISR_OFFSET);
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+ }
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+
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/* drop byte with parity error if IGNPAR specified */
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if (isrstatus & port->ignore_status_mask & XUARTPS_IXR_PARITY)
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isrstatus &= ~(XUARTPS_IXR_RXTRIG | XUARTPS_IXR_TOUT);
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@@ -184,6 +230,30 @@ static irqreturn_t xuartps_isr(int irq, void *dev_id)
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while ((xuartps_readl(XUARTPS_SR_OFFSET) &
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XUARTPS_SR_RXEMPTY) != XUARTPS_SR_RXEMPTY) {
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data = xuartps_readl(XUARTPS_FIFO_OFFSET);
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+
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+ /* Non-NULL byte after BREAK is garbage (99%) */
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+ if (data && (port->read_status_mask &
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+ XUARTPS_IXR_BRK)) {
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+ port->read_status_mask &= ~XUARTPS_IXR_BRK;
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+ port->icount.brk++;
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+ if (uart_handle_break(port))
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+ continue;
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+ }
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+
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+ /*
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+ * uart_handle_sysrq_char() doesn't work if
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+ * spinlocked, for some reason
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+ */
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+ if (port->sysrq) {
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+ spin_unlock(&port->lock);
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+ if (uart_handle_sysrq_char(port,
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+ (unsigned char)data)) {
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+ spin_lock(&port->lock);
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+ continue;
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+ }
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+ spin_lock(&port->lock);
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+ }
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+
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port->icount.rx++;
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if (isrstatus & XUARTPS_IXR_PARITY) {
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@@ -247,63 +317,196 @@ static irqreturn_t xuartps_isr(int irq, void *dev_id)
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}
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/**
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- * xuartps_set_baud_rate - Calculate and set the baud rate
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- * @port: Handle to the uart port structure
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- * @baud: Baud rate to set
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- *
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+ * xuartps_calc_baud_divs - Calculate baud rate divisors
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+ * @clk: UART module input clock
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+ * @baud: Desired baud rate
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+ * @rbdiv: BDIV value (return value)
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+ * @rcd: CD value (return value)
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+ * @div8: Value for clk_sel bit in mod (return value)
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* Returns baud rate, requested baud when possible, or actual baud when there
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- * was too much error
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- **/
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-static unsigned int xuartps_set_baud_rate(struct uart_port *port,
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- unsigned int baud)
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+ * was too much error, zero if no valid divisors are found.
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+ *
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+ * Formula to obtain baud rate is
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+ * baud_tx/rx rate = clk/CD * (BDIV + 1)
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+ * input_clk = (Uart User Defined Clock or Apb Clock)
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+ * depends on UCLKEN in MR Reg
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+ * clk = input_clk or input_clk/8;
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+ * depends on CLKS in MR reg
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+ * CD and BDIV depends on values in
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+ * baud rate generate register
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+ * baud rate clock divisor register
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+ */
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+static unsigned int xuartps_calc_baud_divs(unsigned int clk, unsigned int baud,
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+ u32 *rbdiv, u32 *rcd, int *div8)
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{
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- unsigned int sel_clk;
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- unsigned int calc_baud = 0;
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- unsigned int brgr_val, brdiv_val;
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+ u32 cd, bdiv;
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+ unsigned int calc_baud;
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+ unsigned int bestbaud = 0;
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unsigned int bauderror;
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+ unsigned int besterror = ~0;
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- /* Formula to obtain baud rate is
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- * baud_tx/rx rate = sel_clk/CD * (BDIV + 1)
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- * input_clk = (Uart User Defined Clock or Apb Clock)
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- * depends on UCLKEN in MR Reg
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- * sel_clk = input_clk or input_clk/8;
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- * depends on CLKS in MR reg
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- * CD and BDIV depends on values in
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- * baud rate generate register
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- * baud rate clock divisor register
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- */
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- sel_clk = port->uartclk;
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- if (xuartps_readl(XUARTPS_MR_OFFSET) & XUARTPS_MR_CLKSEL)
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- sel_clk = sel_clk / 8;
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-
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- /* Find the best values for baud generation */
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- for (brdiv_val = 4; brdiv_val < 255; brdiv_val++) {
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+ if (baud < clk / ((XUARTPS_BDIV_MAX + 1) * XUARTPS_CD_MAX)) {
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+ *div8 = 1;
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+ clk /= 8;
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+ } else {
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+ *div8 = 0;
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+ }
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- brgr_val = sel_clk / (baud * (brdiv_val + 1));
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- if (brgr_val < 2 || brgr_val > 65535)
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+ for (bdiv = XUARTPS_BDIV_MIN; bdiv <= XUARTPS_BDIV_MAX; bdiv++) {
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+ cd = DIV_ROUND_CLOSEST(clk, baud * (bdiv + 1));
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+ if (cd < 1 || cd > XUARTPS_CD_MAX)
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continue;
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- calc_baud = sel_clk / (brgr_val * (brdiv_val + 1));
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+ calc_baud = clk / (cd * (bdiv + 1));
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if (baud > calc_baud)
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bauderror = baud - calc_baud;
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else
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bauderror = calc_baud - baud;
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- /* use the values when percent error is acceptable */
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- if (((bauderror * 100) / baud) < 3) {
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- calc_baud = baud;
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- break;
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+ if (besterror > bauderror) {
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+ *rbdiv = bdiv;
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+ *rcd = cd;
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+ bestbaud = calc_baud;
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+ besterror = bauderror;
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}
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}
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+ /* use the values when percent error is acceptable */
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+ if (((besterror * 100) / baud) < 3)
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+ bestbaud = baud;
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+
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+ return bestbaud;
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+}
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- /* Set the values for the new baud rate */
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- xuartps_writel(brgr_val, XUARTPS_BAUDGEN_OFFSET);
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- xuartps_writel(brdiv_val, XUARTPS_BAUDDIV_OFFSET);
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+/**
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+ * xuartps_set_baud_rate - Calculate and set the baud rate
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+ * @port: Handle to the uart port structure
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+ * @baud: Baud rate to set
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+ * Returns baud rate, requested baud when possible, or actual baud when there
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+ * was too much error, zero if no valid divisors are found.
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+ */
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+static unsigned int xuartps_set_baud_rate(struct uart_port *port,
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+ unsigned int baud)
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+{
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+ unsigned int calc_baud;
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+ u32 cd = 0, bdiv = 0;
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+ u32 mreg;
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+ int div8;
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+ struct xuartps *xuartps = port->private_data;
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+
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+ calc_baud = xuartps_calc_baud_divs(port->uartclk, baud, &bdiv, &cd,
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+ &div8);
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+
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+ /* Write new divisors to hardware */
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+ mreg = xuartps_readl(XUARTPS_MR_OFFSET);
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+ if (div8)
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+ mreg |= XUARTPS_MR_CLKSEL;
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+ else
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+ mreg &= ~XUARTPS_MR_CLKSEL;
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+ xuartps_writel(mreg, XUARTPS_MR_OFFSET);
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+ xuartps_writel(cd, XUARTPS_BAUDGEN_OFFSET);
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+ xuartps_writel(bdiv, XUARTPS_BAUDDIV_OFFSET);
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+ xuartps->baud = baud;
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return calc_baud;
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}
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+#ifdef CONFIG_COMMON_CLK
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+/**
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+ * xuartps_clk_notitifer_cb - Clock notifier callback
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+ * @nb: Notifier block
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+ * @event: Notify event
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+ * @data: Notifier data
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+ * Returns NOTIFY_OK on success, NOTIFY_BAD on error.
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+ */
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+static int xuartps_clk_notifier_cb(struct notifier_block *nb,
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+ unsigned long event, void *data)
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+{
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+ u32 ctrl_reg;
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+ struct uart_port *port;
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+ int locked = 0;
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+ struct clk_notifier_data *ndata = data;
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+ unsigned long flags = 0;
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+ struct xuartps *xuartps = to_xuartps(nb);
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+
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+ port = xuartps->port;
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+ if (port->suspended)
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+ return NOTIFY_OK;
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+
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+ switch (event) {
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+ case PRE_RATE_CHANGE:
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+ {
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+ u32 bdiv;
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+ u32 cd;
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+ int div8;
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+
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+ /*
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+ * Find out if current baud-rate can be achieved with new clock
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+ * frequency.
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+ */
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+ if (!xuartps_calc_baud_divs(ndata->new_rate, xuartps->baud,
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+ &bdiv, &cd, &div8))
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+ return NOTIFY_BAD;
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+
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+ spin_lock_irqsave(&xuartps->port->lock, flags);
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+
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+ /* Disable the TX and RX to set baud rate */
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+ xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) |
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+ (XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS),
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+ XUARTPS_CR_OFFSET);
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+
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+ spin_unlock_irqrestore(&xuartps->port->lock, flags);
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+
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+ return NOTIFY_OK;
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+ }
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+ case POST_RATE_CHANGE:
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+ /*
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+ * Set clk dividers to generate correct baud with new clock
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+ * frequency.
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+ */
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+
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+ spin_lock_irqsave(&xuartps->port->lock, flags);
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+
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+ locked = 1;
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+ port->uartclk = ndata->new_rate;
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+
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+ xuartps->baud = xuartps_set_baud_rate(xuartps->port,
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+ xuartps->baud);
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+ /* fall through */
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+ case ABORT_RATE_CHANGE:
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+ if (!locked)
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+ spin_lock_irqsave(&xuartps->port->lock, flags);
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+
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+ /* Set TX/RX Reset */
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+ xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) |
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+ (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST),
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+ XUARTPS_CR_OFFSET);
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+
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+ while (xuartps_readl(XUARTPS_CR_OFFSET) &
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+ (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST))
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+ cpu_relax();
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+
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+ /*
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+ * Clear the RX disable and TX disable bits and then set the TX
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+ * enable bit and RX enable bit to enable the transmitter and
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+ * receiver.
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+ */
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+ xuartps_writel(rx_timeout, XUARTPS_RXTOUT_OFFSET);
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+ ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
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+ xuartps_writel(
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+ (ctrl_reg & ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS)) |
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+ (XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN),
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+ XUARTPS_CR_OFFSET);
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+
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+ spin_unlock_irqrestore(&xuartps->port->lock, flags);
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+
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+ return NOTIFY_OK;
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+ default:
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+ return NOTIFY_DONE;
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+ }
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+}
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+#endif
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+
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/*----------------------Uart Operations---------------------------*/
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/**
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@@ -346,7 +549,7 @@ static void xuartps_start_tx(struct uart_port *port)
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port->state->xmit.tail = (port->state->xmit.tail + 1) &
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(UART_XMIT_SIZE - 1);
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}
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-
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+ xuartps_writel(XUARTPS_IXR_TXEMPTY, XUARTPS_ISR_OFFSET);
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/* Enable the TX Empty interrupt */
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xuartps_writel(XUARTPS_IXR_TXEMPTY, XUARTPS_IER_OFFSET);
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@@ -437,7 +640,7 @@ static void xuartps_set_termios(struct uart_port *port,
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struct ktermios *termios, struct ktermios *old)
|
|
|
{
|
|
|
unsigned int cval = 0;
|
|
|
- unsigned int baud;
|
|
|
+ unsigned int baud, minbaud, maxbaud;
|
|
|
unsigned long flags;
|
|
|
unsigned int ctrl_reg, mode_reg;
|
|
|
|
|
@@ -454,8 +657,14 @@ static void xuartps_set_termios(struct uart_port *port,
|
|
|
(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS),
|
|
|
XUARTPS_CR_OFFSET);
|
|
|
|
|
|
- /* Min baud rate = 6bps and Max Baud Rate is 10Mbps for 100Mhz clk */
|
|
|
- baud = uart_get_baud_rate(port, termios, old, 0, 10000000);
|
|
|
+ /*
|
|
|
+ * Min baud rate = 6bps and Max Baud Rate is 10Mbps for 100Mhz clk
|
|
|
+ * min and max baud should be calculated here based on port->uartclk.
|
|
|
+ * this way we get a valid baud and can safely call set_baud()
|
|
|
+ */
|
|
|
+ minbaud = port->uartclk / ((XUARTPS_BDIV_MAX + 1) * XUARTPS_CD_MAX * 8);
|
|
|
+ maxbaud = port->uartclk / (XUARTPS_BDIV_MIN + 1);
|
|
|
+ baud = uart_get_baud_rate(port, termios, old, minbaud, maxbaud);
|
|
|
baud = xuartps_set_baud_rate(port, baud);
|
|
|
if (tty_termios_baud_rate(termios))
|
|
|
tty_termios_encode_baud_rate(termios, baud, baud);
|
|
@@ -480,7 +689,7 @@ static void xuartps_set_termios(struct uart_port *port,
|
|
|
| (XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN),
|
|
|
XUARTPS_CR_OFFSET);
|
|
|
|
|
|
- xuartps_writel(10, XUARTPS_RXTOUT_OFFSET);
|
|
|
+ xuartps_writel(rx_timeout, XUARTPS_RXTOUT_OFFSET);
|
|
|
|
|
|
port->read_status_mask = XUARTPS_IXR_TXEMPTY | XUARTPS_IXR_RXTRIG |
|
|
|
XUARTPS_IXR_OVERRUN | XUARTPS_IXR_TOUT;
|
|
@@ -531,13 +740,17 @@ static void xuartps_set_termios(struct uart_port *port,
|
|
|
cval |= XUARTPS_MR_PARITY_MARK;
|
|
|
else
|
|
|
cval |= XUARTPS_MR_PARITY_SPACE;
|
|
|
- } else if (termios->c_cflag & PARODD)
|
|
|
+ } else {
|
|
|
+ if (termios->c_cflag & PARODD)
|
|
|
cval |= XUARTPS_MR_PARITY_ODD;
|
|
|
else
|
|
|
cval |= XUARTPS_MR_PARITY_EVEN;
|
|
|
- } else
|
|
|
+ }
|
|
|
+ } else {
|
|
|
cval |= XUARTPS_MR_PARITY_NONE;
|
|
|
- xuartps_writel(cval , XUARTPS_MR_OFFSET);
|
|
|
+ }
|
|
|
+ cval |= mode_reg & 1;
|
|
|
+ xuartps_writel(cval, XUARTPS_MR_OFFSET);
|
|
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
|
}
|
|
@@ -583,11 +796,17 @@ static int xuartps_startup(struct uart_port *port)
|
|
|
| XUARTPS_MR_PARITY_NONE | XUARTPS_MR_CHARLEN_8_BIT,
|
|
|
XUARTPS_MR_OFFSET);
|
|
|
|
|
|
- /* Set the RX FIFO Trigger level to 14 assuming FIFO size as 16 */
|
|
|
- xuartps_writel(14, XUARTPS_RXWM_OFFSET);
|
|
|
+ /*
|
|
|
+ * Set the RX FIFO Trigger level to use most of the FIFO, but it
|
|
|
+ * can be tuned with a module parameter
|
|
|
+ */
|
|
|
+ xuartps_writel(rx_trigger_level, XUARTPS_RXWM_OFFSET);
|
|
|
|
|
|
- /* Receive Timeout register is enabled with value of 10 */
|
|
|
- xuartps_writel(10, XUARTPS_RXTOUT_OFFSET);
|
|
|
+ /*
|
|
|
+ * Receive Timeout register is enabled but it
|
|
|
+ * can be tuned with a module parameter
|
|
|
+ */
|
|
|
+ xuartps_writel(rx_timeout, XUARTPS_RXTOUT_OFFSET);
|
|
|
|
|
|
/* Clear out any pending interrupts before enabling them */
|
|
|
xuartps_writel(xuartps_readl(XUARTPS_ISR_OFFSET), XUARTPS_ISR_OFFSET);
|
|
@@ -727,6 +946,54 @@ static void xuartps_enable_ms(struct uart_port *port)
|
|
|
/* N/A */
|
|
|
}
|
|
|
|
|
|
+#ifdef CONFIG_CONSOLE_POLL
|
|
|
+static int xuartps_poll_get_char(struct uart_port *port)
|
|
|
+{
|
|
|
+ u32 imr;
|
|
|
+ int c;
|
|
|
+
|
|
|
+ /* Disable all interrupts */
|
|
|
+ imr = xuartps_readl(XUARTPS_IMR_OFFSET);
|
|
|
+ xuartps_writel(imr, XUARTPS_IDR_OFFSET);
|
|
|
+
|
|
|
+ /* Check if FIFO is empty */
|
|
|
+ if (xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_RXEMPTY)
|
|
|
+ c = NO_POLL_CHAR;
|
|
|
+ else /* Read a character */
|
|
|
+ c = (unsigned char) xuartps_readl(XUARTPS_FIFO_OFFSET);
|
|
|
+
|
|
|
+ /* Enable interrupts */
|
|
|
+ xuartps_writel(imr, XUARTPS_IER_OFFSET);
|
|
|
+
|
|
|
+ return c;
|
|
|
+}
|
|
|
+
|
|
|
+static void xuartps_poll_put_char(struct uart_port *port, unsigned char c)
|
|
|
+{
|
|
|
+ u32 imr;
|
|
|
+
|
|
|
+ /* Disable all interrupts */
|
|
|
+ imr = xuartps_readl(XUARTPS_IMR_OFFSET);
|
|
|
+ xuartps_writel(imr, XUARTPS_IDR_OFFSET);
|
|
|
+
|
|
|
+ /* Wait until FIFO is empty */
|
|
|
+ while (!(xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_TXEMPTY))
|
|
|
+ cpu_relax();
|
|
|
+
|
|
|
+ /* Write a character */
|
|
|
+ xuartps_writel(c, XUARTPS_FIFO_OFFSET);
|
|
|
+
|
|
|
+ /* Wait until FIFO is empty */
|
|
|
+ while (!(xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_TXEMPTY))
|
|
|
+ cpu_relax();
|
|
|
+
|
|
|
+ /* Enable interrupts */
|
|
|
+ xuartps_writel(imr, XUARTPS_IER_OFFSET);
|
|
|
+
|
|
|
+ return;
|
|
|
+}
|
|
|
+#endif
|
|
|
+
|
|
|
/** The UART operations structure
|
|
|
*/
|
|
|
static struct uart_ops xuartps_ops = {
|
|
@@ -759,6 +1026,10 @@ static struct uart_ops xuartps_ops = {
|
|
|
.config_port = xuartps_config_port, /* Configure when driver
|
|
|
* adds a xuartps port
|
|
|
*/
|
|
|
+#ifdef CONFIG_CONSOLE_POLL
|
|
|
+ .poll_get_char = xuartps_poll_get_char,
|
|
|
+ .poll_put_char = xuartps_poll_put_char,
|
|
|
+#endif
|
|
|
};
|
|
|
|
|
|
static struct uart_port xuartps_port[2];
|
|
@@ -837,7 +1108,7 @@ static void xuartps_console_write(struct console *co, const char *s,
|
|
|
{
|
|
|
struct uart_port *port = &xuartps_port[co->index];
|
|
|
unsigned long flags;
|
|
|
- unsigned int imr;
|
|
|
+ unsigned int imr, ctrl;
|
|
|
int locked = 1;
|
|
|
|
|
|
if (oops_in_progress)
|
|
@@ -849,9 +1120,19 @@ static void xuartps_console_write(struct console *co, const char *s,
|
|
|
imr = xuartps_readl(XUARTPS_IMR_OFFSET);
|
|
|
xuartps_writel(imr, XUARTPS_IDR_OFFSET);
|
|
|
|
|
|
+ /*
|
|
|
+ * Make sure that the tx part is enabled. Set the TX enable bit and
|
|
|
+ * clear the TX disable bit to enable the transmitter.
|
|
|
+ */
|
|
|
+ ctrl = xuartps_readl(XUARTPS_CR_OFFSET);
|
|
|
+ xuartps_writel((ctrl & ~XUARTPS_CR_TX_DIS) | XUARTPS_CR_TX_EN,
|
|
|
+ XUARTPS_CR_OFFSET);
|
|
|
+
|
|
|
uart_console_write(port, s, count, xuartps_console_putchar);
|
|
|
xuartps_console_wait_tx(port);
|
|
|
|
|
|
+ xuartps_writel(ctrl, XUARTPS_CR_OFFSET);
|
|
|
+
|
|
|
/* restore interrupt state, it seems like there may be a h/w bug
|
|
|
* in that the interrupt enable register should not need to be
|
|
|
* written based on the data sheet
|
|
@@ -933,6 +1214,119 @@ static struct uart_driver xuartps_uart_driver = {
|
|
|
#endif
|
|
|
};
|
|
|
|
|
|
+#ifdef CONFIG_PM_SLEEP
|
|
|
+/**
|
|
|
+ * xuartps_suspend - suspend event
|
|
|
+ * @device: Pointer to the device structure
|
|
|
+ *
|
|
|
+ * Returns 0
|
|
|
+ */
|
|
|
+static int xuartps_suspend(struct device *device)
|
|
|
+{
|
|
|
+ struct uart_port *port = dev_get_drvdata(device);
|
|
|
+ struct tty_struct *tty;
|
|
|
+ struct device *tty_dev;
|
|
|
+ int may_wake = 0;
|
|
|
+
|
|
|
+ /* Get the tty which could be NULL so don't assume it's valid */
|
|
|
+ tty = tty_port_tty_get(&port->state->port);
|
|
|
+ if (tty) {
|
|
|
+ tty_dev = tty->dev;
|
|
|
+ may_wake = device_may_wakeup(tty_dev);
|
|
|
+ tty_kref_put(tty);
|
|
|
+ }
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Call the API provided in serial_core.c file which handles
|
|
|
+ * the suspend.
|
|
|
+ */
|
|
|
+ uart_suspend_port(&xuartps_uart_driver, port);
|
|
|
+ if (console_suspend_enabled && !may_wake) {
|
|
|
+ struct xuartps *xuartps = port->private_data;
|
|
|
+
|
|
|
+ clk_disable(xuartps->refclk);
|
|
|
+ clk_disable(xuartps->aperclk);
|
|
|
+ } else {
|
|
|
+ unsigned long flags = 0;
|
|
|
+
|
|
|
+ spin_lock_irqsave(&port->lock, flags);
|
|
|
+ /* Empty the receive FIFO 1st before making changes */
|
|
|
+ while (!(xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_RXEMPTY))
|
|
|
+ xuartps_readl(XUARTPS_FIFO_OFFSET);
|
|
|
+ /* set RX trigger level to 1 */
|
|
|
+ xuartps_writel(1, XUARTPS_RXWM_OFFSET);
|
|
|
+ /* disable RX timeout interrups */
|
|
|
+ xuartps_writel(XUARTPS_IXR_TOUT, XUARTPS_IDR_OFFSET);
|
|
|
+ spin_unlock_irqrestore(&port->lock, flags);
|
|
|
+ }
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * xuartps_resume - Resume after a previous suspend
|
|
|
+ * @device: Pointer to the device structure
|
|
|
+ *
|
|
|
+ * Returns 0
|
|
|
+ */
|
|
|
+static int xuartps_resume(struct device *device)
|
|
|
+{
|
|
|
+ struct uart_port *port = dev_get_drvdata(device);
|
|
|
+ unsigned long flags = 0;
|
|
|
+ u32 ctrl_reg;
|
|
|
+ struct tty_struct *tty;
|
|
|
+ struct device *tty_dev;
|
|
|
+ int may_wake = 0;
|
|
|
+
|
|
|
+ /* Get the tty which could be NULL so don't assume it's valid */
|
|
|
+ tty = tty_port_tty_get(&port->state->port);
|
|
|
+ if (tty) {
|
|
|
+ tty_dev = tty->dev;
|
|
|
+ may_wake = device_may_wakeup(tty_dev);
|
|
|
+ tty_kref_put(tty);
|
|
|
+ }
|
|
|
+
|
|
|
+ if (console_suspend_enabled && !may_wake) {
|
|
|
+ struct xuartps *xuartps = port->private_data;
|
|
|
+
|
|
|
+ clk_enable(xuartps->aperclk);
|
|
|
+ clk_enable(xuartps->refclk);
|
|
|
+
|
|
|
+ spin_lock_irqsave(&port->lock, flags);
|
|
|
+
|
|
|
+ /* Set TX/RX Reset */
|
|
|
+ xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) |
|
|
|
+ (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST),
|
|
|
+ XUARTPS_CR_OFFSET);
|
|
|
+ while (xuartps_readl(XUARTPS_CR_OFFSET) &
|
|
|
+ (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST))
|
|
|
+ cpu_relax();
|
|
|
+
|
|
|
+ /* restore rx timeout value */
|
|
|
+ xuartps_writel(rx_timeout, XUARTPS_RXTOUT_OFFSET);
|
|
|
+ /* Enable Tx/Rx */
|
|
|
+ ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
|
|
|
+ xuartps_writel(
|
|
|
+ (ctrl_reg & ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS)) |
|
|
|
+ (XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN),
|
|
|
+ XUARTPS_CR_OFFSET);
|
|
|
+
|
|
|
+ spin_unlock_irqrestore(&port->lock, flags);
|
|
|
+ } else {
|
|
|
+ spin_lock_irqsave(&port->lock, flags);
|
|
|
+ /* restore original rx trigger level */
|
|
|
+ xuartps_writel(rx_trigger_level, XUARTPS_RXWM_OFFSET);
|
|
|
+ /* enable RX timeout interrupt */
|
|
|
+ xuartps_writel(XUARTPS_IXR_TOUT, XUARTPS_IER_OFFSET);
|
|
|
+ spin_unlock_irqrestore(&port->lock, flags);
|
|
|
+ }
|
|
|
+
|
|
|
+ return uart_resume_port(&xuartps_uart_driver, port);
|
|
|
+}
|
|
|
+#endif /* ! CONFIG_PM_SLEEP */
|
|
|
+
|
|
|
+static SIMPLE_DEV_PM_OPS(xuartps_dev_pm_ops, xuartps_suspend, xuartps_resume);
|
|
|
+
|
|
|
/* ---------------------------------------------------------------------
|
|
|
* Platform bus binding
|
|
|
*/
|
|
@@ -949,27 +1343,26 @@ static int xuartps_probe(struct platform_device *pdev)
|
|
|
struct resource *res, *res2;
|
|
|
struct xuartps *xuartps_data;
|
|
|
|
|
|
- xuartps_data = kzalloc(sizeof(*xuartps_data), GFP_KERNEL);
|
|
|
+ xuartps_data = devm_kzalloc(&pdev->dev, sizeof(*xuartps_data),
|
|
|
+ GFP_KERNEL);
|
|
|
if (!xuartps_data)
|
|
|
return -ENOMEM;
|
|
|
|
|
|
- xuartps_data->aperclk = clk_get(&pdev->dev, "aper_clk");
|
|
|
+ xuartps_data->aperclk = devm_clk_get(&pdev->dev, "aper_clk");
|
|
|
if (IS_ERR(xuartps_data->aperclk)) {
|
|
|
dev_err(&pdev->dev, "aper_clk clock not found.\n");
|
|
|
- rc = PTR_ERR(xuartps_data->aperclk);
|
|
|
- goto err_out_free;
|
|
|
+ return PTR_ERR(xuartps_data->aperclk);
|
|
|
}
|
|
|
- xuartps_data->refclk = clk_get(&pdev->dev, "ref_clk");
|
|
|
+ xuartps_data->refclk = devm_clk_get(&pdev->dev, "ref_clk");
|
|
|
if (IS_ERR(xuartps_data->refclk)) {
|
|
|
dev_err(&pdev->dev, "ref_clk clock not found.\n");
|
|
|
- rc = PTR_ERR(xuartps_data->refclk);
|
|
|
- goto err_out_clk_put_aper;
|
|
|
+ return PTR_ERR(xuartps_data->refclk);
|
|
|
}
|
|
|
|
|
|
rc = clk_prepare_enable(xuartps_data->aperclk);
|
|
|
if (rc) {
|
|
|
dev_err(&pdev->dev, "Unable to enable APER clock.\n");
|
|
|
- goto err_out_clk_put;
|
|
|
+ return rc;
|
|
|
}
|
|
|
rc = clk_prepare_enable(xuartps_data->refclk);
|
|
|
if (rc) {
|
|
@@ -989,13 +1382,21 @@ static int xuartps_probe(struct platform_device *pdev)
|
|
|
goto err_out_clk_disable;
|
|
|
}
|
|
|
|
|
|
+#ifdef CONFIG_COMMON_CLK
|
|
|
+ xuartps_data->clk_rate_change_nb.notifier_call =
|
|
|
+ xuartps_clk_notifier_cb;
|
|
|
+ if (clk_notifier_register(xuartps_data->refclk,
|
|
|
+ &xuartps_data->clk_rate_change_nb))
|
|
|
+ dev_warn(&pdev->dev, "Unable to register clock notifier.\n");
|
|
|
+#endif
|
|
|
+
|
|
|
/* Initialize the port structure */
|
|
|
port = xuartps_get_port();
|
|
|
|
|
|
if (!port) {
|
|
|
dev_err(&pdev->dev, "Cannot get uart_port structure\n");
|
|
|
rc = -ENODEV;
|
|
|
- goto err_out_clk_disable;
|
|
|
+ goto err_out_notif_unreg;
|
|
|
} else {
|
|
|
/* Register the port.
|
|
|
* This function also registers this device with the tty layer
|
|
@@ -1006,26 +1407,26 @@ static int xuartps_probe(struct platform_device *pdev)
|
|
|
port->dev = &pdev->dev;
|
|
|
port->uartclk = clk_get_rate(xuartps_data->refclk);
|
|
|
port->private_data = xuartps_data;
|
|
|
+ xuartps_data->port = port;
|
|
|
platform_set_drvdata(pdev, port);
|
|
|
rc = uart_add_one_port(&xuartps_uart_driver, port);
|
|
|
if (rc) {
|
|
|
dev_err(&pdev->dev,
|
|
|
"uart_add_one_port() failed; err=%i\n", rc);
|
|
|
- goto err_out_clk_disable;
|
|
|
+ goto err_out_notif_unreg;
|
|
|
}
|
|
|
return 0;
|
|
|
}
|
|
|
|
|
|
+err_out_notif_unreg:
|
|
|
+#ifdef CONFIG_COMMON_CLK
|
|
|
+ clk_notifier_unregister(xuartps_data->refclk,
|
|
|
+ &xuartps_data->clk_rate_change_nb);
|
|
|
+#endif
|
|
|
err_out_clk_disable:
|
|
|
clk_disable_unprepare(xuartps_data->refclk);
|
|
|
err_out_clk_dis_aper:
|
|
|
clk_disable_unprepare(xuartps_data->aperclk);
|
|
|
-err_out_clk_put:
|
|
|
- clk_put(xuartps_data->refclk);
|
|
|
-err_out_clk_put_aper:
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- clk_put(xuartps_data->aperclk);
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-err_out_free:
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- kfree(xuartps_data);
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return rc;
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}
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@@ -1043,13 +1444,14 @@ static int xuartps_remove(struct platform_device *pdev)
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int rc;
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/* Remove the xuartps port from the serial core */
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+#ifdef CONFIG_COMMON_CLK
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+ clk_notifier_unregister(xuartps_data->refclk,
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+ &xuartps_data->clk_rate_change_nb);
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+#endif
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rc = uart_remove_one_port(&xuartps_uart_driver, port);
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port->mapbase = 0;
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clk_disable_unprepare(xuartps_data->refclk);
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clk_disable_unprepare(xuartps_data->aperclk);
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- clk_put(xuartps_data->refclk);
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- clk_put(xuartps_data->aperclk);
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- kfree(xuartps_data);
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return rc;
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}
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@@ -1067,6 +1469,7 @@ static struct platform_driver xuartps_platform_driver = {
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.owner = THIS_MODULE,
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.name = XUARTPS_NAME, /* Driver name */
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.of_match_table = xuartps_of_match,
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+ .pm = &xuartps_dev_pm_ops,
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},
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};
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