From 1543e317f1da31b75942316931e8f491a8920811 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Thu, 04 Jan 2024 10:08:02 +0000
Subject: [PATCH] disable FB
---
kernel/drivers/tty/serial/meson_uart.c | 106 +++++++++++++++++++++++++++++++++++++++++++++++++---
1 files changed, 99 insertions(+), 7 deletions(-)
diff --git a/kernel/drivers/tty/serial/meson_uart.c b/kernel/drivers/tty/serial/meson_uart.c
index 8a84259..3f8ccb8 100644
--- a/kernel/drivers/tty/serial/meson_uart.c
+++ b/kernel/drivers/tty/serial/meson_uart.c
@@ -5,15 +5,12 @@
* Copyright (C) 2014 Carlo Caione <carlo@caione.org>
*/
-#if defined(CONFIG_SERIAL_MESON_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
-#define SUPPORT_SYSRQ
-#endif
-
#include <linux/clk.h>
#include <linux/console.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/of.h>
@@ -72,9 +69,12 @@
#define AML_UART_BAUD_USE BIT(23)
#define AML_UART_BAUD_XTAL BIT(24)
-#define AML_UART_PORT_NUM 6
+#define AML_UART_PORT_NUM 12
+#define AML_UART_PORT_OFFSET 6
#define AML_UART_DEV_NAME "ttyAML"
+#define AML_UART_POLL_USEC 5
+#define AML_UART_TIMEOUT_USEC 10000
static struct uart_driver meson_uart_driver;
@@ -255,6 +255,14 @@
return (port->type == PORT_MESON) ? "meson_uart" : NULL;
}
+/*
+ * This function is called only from probe() using a temporary io mapping
+ * in order to perform a reset before setting up the device. Since the
+ * temporarily mapped region was successfully requested, there can be no
+ * console on this port at this time. Hence it is not necessary for this
+ * function to acquire the port->lock. (Since there is no console on this
+ * port at this time, the port->lock is not initialized yet.)
+ */
static void meson_uart_reset(struct uart_port *port)
{
u32 val;
@@ -269,8 +277,11 @@
static int meson_uart_startup(struct uart_port *port)
{
+ unsigned long flags;
u32 val;
int ret = 0;
+
+ spin_lock_irqsave(&port->lock, flags);
val = readl(port->membase + AML_UART_CONTROL);
val |= AML_UART_CLEAR_ERR;
@@ -286,6 +297,8 @@
val = (AML_UART_RECV_IRQ(1) | AML_UART_XMIT_IRQ(port->fifosize / 2));
writel(val, port->membase + AML_UART_MISC);
+
+ spin_unlock_irqrestore(&port->lock, flags);
ret = request_irq(port->irq, meson_uart_interrupt, 0,
port->name, port);
@@ -410,7 +423,7 @@
return -EBUSY;
}
- port->membase = devm_ioremap_nocache(port->dev, port->mapbase,
+ port->membase = devm_ioremap(port->dev, port->mapbase,
port->mapsize);
if (!port->membase)
return -ENOMEM;
@@ -425,6 +438,64 @@
meson_uart_request_port(port);
}
}
+
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * Console polling routines for writing and reading from the uart while
+ * in an interrupt or debug context (i.e. kgdb).
+ */
+
+static int meson_uart_poll_get_char(struct uart_port *port)
+{
+ u32 c;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ if (readl(port->membase + AML_UART_STATUS) & AML_UART_RX_EMPTY)
+ c = NO_POLL_CHAR;
+ else
+ c = readl(port->membase + AML_UART_RFIFO);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ return c;
+}
+
+static void meson_uart_poll_put_char(struct uart_port *port, unsigned char c)
+{
+ unsigned long flags;
+ u32 reg;
+ int ret;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* Wait until FIFO is empty or timeout */
+ ret = readl_poll_timeout_atomic(port->membase + AML_UART_STATUS, reg,
+ reg & AML_UART_TX_EMPTY,
+ AML_UART_POLL_USEC,
+ AML_UART_TIMEOUT_USEC);
+ if (ret == -ETIMEDOUT) {
+ dev_err(port->dev, "Timeout waiting for UART TX EMPTY\n");
+ goto out;
+ }
+
+ /* Write the character */
+ writel(c, port->membase + AML_UART_WFIFO);
+
+ /* Wait until FIFO is empty or timeout */
+ ret = readl_poll_timeout_atomic(port->membase + AML_UART_STATUS, reg,
+ reg & AML_UART_TX_EMPTY,
+ AML_UART_POLL_USEC,
+ AML_UART_TIMEOUT_USEC);
+ if (ret == -ETIMEDOUT)
+ dev_err(port->dev, "Timeout waiting for UART TX EMPTY\n");
+
+out:
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+#endif /* CONFIG_CONSOLE_POLL */
static const struct uart_ops meson_uart_ops = {
.set_mctrl = meson_uart_set_mctrl,
@@ -441,6 +512,10 @@
.request_port = meson_uart_request_port,
.release_port = meson_uart_release_port,
.verify_port = meson_uart_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = meson_uart_poll_get_char,
+ .poll_put_char = meson_uart_poll_put_char,
+#endif
};
#ifdef CONFIG_SERIAL_MESON_CONSOLE
@@ -542,7 +617,6 @@
register_console(&meson_serial_console);
return 0;
}
-console_initcall(meson_serial_console_init);
static void meson_serial_early_console_write(struct console *co,
const char *s,
@@ -572,6 +646,9 @@
#define MESON_SERIAL_CONSOLE (&meson_serial_console)
#else
+static int __init meson_serial_console_init(void) {
+ return 0;
+}
#define MESON_SERIAL_CONSOLE NULL
#endif
@@ -654,9 +731,19 @@
struct resource *res_mem, *res_irq;
struct uart_port *port;
int ret = 0;
+ int id = -1;
if (pdev->dev.of_node)
pdev->id = of_alias_get_id(pdev->dev.of_node, "serial");
+
+ if (pdev->id < 0) {
+ for (id = AML_UART_PORT_OFFSET; id < AML_UART_PORT_NUM; id++) {
+ if (!meson_ports[id]) {
+ pdev->id = id;
+ break;
+ }
+ }
+ }
if (pdev->id < 0 || pdev->id >= AML_UART_PORT_NUM)
return -EINVAL;
@@ -692,6 +779,7 @@
port->mapsize = resource_size(res_mem);
port->irq = res_irq->start;
port->flags = UPF_BOOT_AUTOCONF | UPF_LOW_LATENCY;
+ port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_MESON_CONSOLE);
port->dev = &pdev->dev;
port->line = pdev->id;
port->type = PORT_MESON;
@@ -751,6 +839,10 @@
{
int ret;
+ ret = meson_serial_console_init();
+ if (ret)
+ return ret;
+
ret = uart_register_driver(&meson_uart_driver);
if (ret)
return ret;
--
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