Jetpack/kernel/nvidia/drivers/platform/tegra/tegra_fiq_debugger.c

347 lines
8.1 KiB
C

/*
* platform/tegra/fiq_debugger.c
*
* Serial Debugger Interface for Tegra
*
* Copyright (C) 2008 Google, Inc.
* Copyright (c) 2012-2018, NVIDIA CORPORATION. All rights reserved.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <stdarg.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <linux/serial_reg.h>
#include <linux/slab.h>
#include <linux/stacktrace.h>
#include <linux/irqchip/tegra.h>
#include <linux/tegra_fiq_debugger.h>
#include <linux/fiq_debugger.h>
#include <linux/uaccess.h>
struct tegra_fiq_debugger {
struct fiq_debugger_pdata pdata;
void __iomem *debug_port_base;
bool break_seen;
};
/* Legacy UART start */
static inline void tegra_write(struct tegra_fiq_debugger *t,
unsigned int val, unsigned int off)
{
__raw_writeb(val, t->debug_port_base + off * 4);
}
static inline unsigned int tegra_read(struct tegra_fiq_debugger *t,
unsigned int off)
{
return __raw_readb(t->debug_port_base + off * 4);
}
static inline unsigned int tegra_read_lsr(struct tegra_fiq_debugger *t)
{
unsigned int lsr;
lsr = tegra_read(t, UART_LSR);
if (lsr & UART_LSR_BI)
t->break_seen = true;
return lsr;
}
static int debug_port_init(struct platform_device *pdev)
{
struct tegra_fiq_debugger *t;
t = container_of(dev_get_platdata(&pdev->dev), typeof(*t), pdata);
if (tegra_read(t, UART_LSR) & UART_LSR_DR)
(void)tegra_read(t, UART_RX);
/* enable rx and lsr interrupt */
tegra_write(t, UART_IER_RLSI | UART_IER_RDI, UART_IER);
/* interrupt on every character */
tegra_write(t, 0, UART_IIR);
return 0;
}
static int debug_getc(struct platform_device *pdev)
{
unsigned int lsr;
struct tegra_fiq_debugger *t;
t = container_of(dev_get_platdata(&pdev->dev), typeof(*t), pdata);
lsr = tegra_read_lsr(t);
if (lsr & UART_LSR_BI || t->break_seen) {
t->break_seen = false;
return FIQ_DEBUGGER_BREAK;
}
if (lsr & UART_LSR_DR)
return tegra_read(t, UART_RX);
return FIQ_DEBUGGER_NO_CHAR;
}
static void debug_putc(struct platform_device *pdev, unsigned int c)
{
struct tegra_fiq_debugger *t;
t = container_of(dev_get_platdata(&pdev->dev), typeof(*t), pdata);
while (!(tegra_read_lsr(t) & UART_LSR_THRE))
cpu_relax();
tegra_write(t, c, UART_TX);
}
static void debug_flush(struct platform_device *pdev)
{
struct tegra_fiq_debugger *t;
t = container_of(dev_get_platdata(&pdev->dev), typeof(*t), pdata);
while (!(tegra_read_lsr(t) & UART_LSR_TEMT))
cpu_relax();
}
static void fiq_enable(struct platform_device *pdev, unsigned int irq, bool on)
{
#ifdef CONFIG_ARM
if (on)
tegra_fiq_enable(irq);
else
tegra_fiq_disable(irq);
#else
; // do nothing
#endif
}
/* Legacy UART end */
/* Combined UART start */
#define CONSOLE_NUM_BYTES_SHIFT 24
#define CONSOLE_FLUSH_DATA_TO_PORT (1 << 26)
#define CONSOLE_RING_DOORBELL (1 << 31)
#define CONSOLE_IS_BUSY (1 << 31)
#define CONSOLE_WRITE (CONSOLE_RING_DOORBELL | \
CONSOLE_FLUSH_DATA_TO_PORT)
static int combined_debug_getc(struct platform_device *pdev)
{
return FIQ_DEBUGGER_NO_CHAR;
}
static void combined_debug_putc(struct platform_device *pdev, unsigned int c)
{
struct tegra_fiq_debugger *t;
unsigned int val;
t = container_of(dev_get_platdata(&pdev->dev), typeof(*t), pdata);
while (__raw_readl(t->debug_port_base) & CONSOLE_IS_BUSY);
val = c;
val |= (CONSOLE_WRITE | (1 << CONSOLE_NUM_BYTES_SHIFT));
__raw_writel(val, t->debug_port_base);
}
static void combined_fiq_enable(struct platform_device *pdev,
unsigned int irq, bool on)
{
#ifdef CONFIG_ARM
if (on)
tegra_fiq_enable(irq);
else
tegra_fiq_disable(irq);
#else
; // do nothing
#endif
}
/* Combined UART end */
static int tegra_fiq_debugger_id;
static bool tegra_fiq_combined_uart;
static void __tegra_serial_debug_init(unsigned int base, int fiq, int irq,
struct clk *clk, int signal_irq, int wakeup_irq)
{
struct tegra_fiq_debugger *t;
struct platform_device *pdev;
struct resource *res;
int res_count;
t = kzalloc(sizeof(struct tegra_fiq_debugger), GFP_KERNEL);
if (!t)
return;
if (tegra_fiq_combined_uart) {
t->pdata.uart_init = NULL;
t->pdata.uart_getc = combined_debug_getc;
t->pdata.uart_putc = combined_debug_putc;
t->pdata.uart_flush = NULL;
t->pdata.fiq_enable = combined_fiq_enable;
} else {
t->pdata.uart_init = debug_port_init;
t->pdata.uart_getc = debug_getc;
t->pdata.uart_putc = debug_putc;
t->pdata.uart_flush = debug_flush;
t->pdata.fiq_enable = fiq_enable;
}
t->debug_port_base = ioremap(base, PAGE_SIZE);
if (!t->debug_port_base) {
pr_err("Failed to ioremap for fiq debugger\n");
goto out1;
}
res = kzalloc(sizeof(struct resource) * 3, GFP_KERNEL);
if (!res)
goto out2;
pdev = kzalloc(sizeof(struct platform_device), GFP_KERNEL);
if (!pdev)
goto out3;
if (fiq >= 0) {
res[0].flags = IORESOURCE_IRQ;
res[0].start = fiq;
res[0].end = fiq;
res[0].name = "fiq";
} else {
res[0].flags = IORESOURCE_IRQ;
res[0].start = irq;
res[0].end = irq;
res[0].name = "uart_irq";
}
res[1].flags = IORESOURCE_IRQ;
res[1].start = signal_irq;
res[1].end = signal_irq;
res[1].name = "signal";
res_count = 2;
if (wakeup_irq >= 0) {
res[2].flags = IORESOURCE_IRQ;
res[2].start = wakeup_irq;
res[2].end = wakeup_irq;
res[2].name = "wakeup";
res_count++;
}
pdev->name = "fiq_debugger";
pdev->id = tegra_fiq_debugger_id++;
pdev->dev.platform_data = &t->pdata;
pdev->resource = res;
pdev->num_resources = res_count;
if (platform_device_register(pdev)) {
pr_err("Failed to register fiq debugger\n");
goto out4;
}
return;
out4:
kfree(pdev);
out3:
kfree(res);
out2:
iounmap(t->debug_port_base);
out1:
kfree(t);
}
void tegra_serial_debug_init(unsigned int base, int fiq,
struct clk *clk, int signal_irq, int wakeup_irq)
{
__tegra_serial_debug_init(base, fiq, -1, clk, signal_irq, wakeup_irq);
}
void tegra_serial_debug_init_irq_mode(unsigned int base, int irq,
struct clk *clk, int signal_irq, int wakeup_irq)
{
__tegra_serial_debug_init(base, -1, irq, clk, signal_irq, wakeup_irq);
}
static int __init tegra_fiq_debugger_init(void)
{
struct device_node *dn, *dn_debugger;
struct resource resource;
unsigned int uartbase = 0;
int irq = -1;
dn_debugger = of_find_compatible_node(NULL, NULL,
"nvidia,fiq-debugger");
if (!dn_debugger) {
pr_err("%s: no fiq_debugger node\n", __func__);
return -ENODEV;
}
/* Search for the IO memory of console port */
if (of_property_read_bool(dn_debugger, "use-console-port")) {
dn = of_find_node_with_property(NULL, "console-port");
if (!dn) {
pr_err("%s: no console-port found\n", __func__);
return -ENODEV;
}
} else
dn = dn_debugger;
if (of_find_node_with_property(NULL, "combined-uart")) {
tegra_fiq_combined_uart = true;
if (of_address_to_resource(dn, 1, &resource)) {
pr_err("%s: could not get IO memory\n", __func__);
return -ENXIO;
}
} else {
tegra_fiq_combined_uart = false;
if (of_address_to_resource(dn, 0, &resource)) {
pr_err("%s: could not get IO memory\n", __func__);
return -ENXIO;
}
}
uartbase = resource.start;
pr_debug("%s: found console port at %08X\n", __func__, uartbase);
/* Search for the interrupt which acts as trigger of FIQ debugger */
if (of_property_read_bool(dn_debugger, "use-wdt-irq")) {
dn = of_find_compatible_node(NULL, NULL, "nvidia,tegra-wdt");
if (!dn) {
pr_err("%s: no tegra-wdt found\n", __func__);
return -ENODEV;
}
} else
dn = dn_debugger;
irq = irq_of_parse_and_map(dn, 0);
if (irq <= 0) {
pr_err("%s: could not find interrupt for FIQ\n", __func__);
return -ENODEV;
}
pr_info("%s: found FIQ source (IRQ %d)\n", __func__, irq);
tegra_serial_debug_init(uartbase, irq, NULL, -1, -1);
return 0;
}
subsys_initcall(tegra_fiq_debugger_init)