mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 02:23:16 +00:00
9192008853
There is a ready-to-use method to compare a retrieved from a sysfs node string with another string. It treats both NUL and newline-then-NUL as equivalent string terminations. So use it instead of manually truncating the line length in the strncmp() method. Link: https://lore.kernel.org/r/20200528145050.5203-6-Sergey.Semin@baikalelectronics.ru Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Cc: Olof Johansson <olof@lixom.net> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: soc@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de>
315 lines
7.1 KiB
C
315 lines
7.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
|
|
*
|
|
* Authors:
|
|
* Serge Semin <Sergey.Semin@baikalelectronics.ru>
|
|
*
|
|
* Baikal-T1 AXI-bus driver
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/bitfield.h>
|
|
#include <linux/device.h>
|
|
#include <linux/atomic.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/mfd/syscon.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/io.h>
|
|
#include <linux/nmi.h>
|
|
#include <linux/of.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/reset.h>
|
|
#include <linux/sysfs.h>
|
|
|
|
#define BT1_AXI_WERRL 0x110
|
|
#define BT1_AXI_WERRH 0x114
|
|
#define BT1_AXI_WERRH_TYPE BIT(23)
|
|
#define BT1_AXI_WERRH_ADDR_FLD 24
|
|
#define BT1_AXI_WERRH_ADDR_MASK GENMASK(31, BT1_AXI_WERRH_ADDR_FLD)
|
|
|
|
/*
|
|
* struct bt1_axi - Baikal-T1 AXI-bus private data
|
|
* @dev: Pointer to the device structure.
|
|
* @qos_regs: AXI Interconnect QoS tuning registers.
|
|
* @sys_regs: Baikal-T1 System Controller registers map.
|
|
* @irq: Errors IRQ number.
|
|
* @aclk: AXI reference clock.
|
|
* @arst: AXI Interconnect reset line.
|
|
* @count: Number of errors detected.
|
|
*/
|
|
struct bt1_axi {
|
|
struct device *dev;
|
|
|
|
void __iomem *qos_regs;
|
|
struct regmap *sys_regs;
|
|
int irq;
|
|
|
|
struct clk *aclk;
|
|
|
|
struct reset_control *arst;
|
|
|
|
atomic_t count;
|
|
};
|
|
|
|
static irqreturn_t bt1_axi_isr(int irq, void *data)
|
|
{
|
|
struct bt1_axi *axi = data;
|
|
u32 low = 0, high = 0;
|
|
|
|
regmap_read(axi->sys_regs, BT1_AXI_WERRL, &low);
|
|
regmap_read(axi->sys_regs, BT1_AXI_WERRH, &high);
|
|
|
|
dev_crit_ratelimited(axi->dev,
|
|
"AXI-bus fault %d: %s at 0x%x%08x\n",
|
|
atomic_inc_return(&axi->count),
|
|
high & BT1_AXI_WERRH_TYPE ? "no slave" : "slave protocol error",
|
|
high, low);
|
|
|
|
/*
|
|
* Print backtrace on each CPU. This might be pointless if the fault
|
|
* has happened on the same CPU as the IRQ handler is executed or
|
|
* the other core proceeded further execution despite the error.
|
|
* But if it's not, by looking at the trace we would get straight to
|
|
* the cause of the problem.
|
|
*/
|
|
trigger_all_cpu_backtrace();
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static void bt1_axi_clear_data(void *data)
|
|
{
|
|
struct bt1_axi *axi = data;
|
|
struct platform_device *pdev = to_platform_device(axi->dev);
|
|
|
|
platform_set_drvdata(pdev, NULL);
|
|
}
|
|
|
|
static struct bt1_axi *bt1_axi_create_data(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct bt1_axi *axi;
|
|
int ret;
|
|
|
|
axi = devm_kzalloc(dev, sizeof(*axi), GFP_KERNEL);
|
|
if (!axi)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
ret = devm_add_action(dev, bt1_axi_clear_data, axi);
|
|
if (ret) {
|
|
dev_err(dev, "Can't add AXI EHB data clear action\n");
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
axi->dev = dev;
|
|
atomic_set(&axi->count, 0);
|
|
platform_set_drvdata(pdev, axi);
|
|
|
|
return axi;
|
|
}
|
|
|
|
static int bt1_axi_request_regs(struct bt1_axi *axi)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(axi->dev);
|
|
struct device *dev = axi->dev;
|
|
|
|
axi->sys_regs = syscon_regmap_lookup_by_phandle(dev->of_node, "syscon");
|
|
if (IS_ERR(axi->sys_regs)) {
|
|
dev_err(dev, "Couldn't find syscon registers\n");
|
|
return PTR_ERR(axi->sys_regs);
|
|
}
|
|
|
|
axi->qos_regs = devm_platform_ioremap_resource_byname(pdev, "qos");
|
|
if (IS_ERR(axi->qos_regs))
|
|
dev_err(dev, "Couldn't map AXI-bus QoS registers\n");
|
|
|
|
return PTR_ERR_OR_ZERO(axi->qos_regs);
|
|
}
|
|
|
|
static int bt1_axi_request_rst(struct bt1_axi *axi)
|
|
{
|
|
int ret;
|
|
|
|
axi->arst = devm_reset_control_get_optional_exclusive(axi->dev, "arst");
|
|
if (IS_ERR(axi->arst)) {
|
|
dev_warn(axi->dev, "Couldn't get reset control line\n");
|
|
return PTR_ERR(axi->arst);
|
|
}
|
|
|
|
ret = reset_control_deassert(axi->arst);
|
|
if (ret)
|
|
dev_err(axi->dev, "Failed to deassert the reset line\n");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void bt1_axi_disable_clk(void *data)
|
|
{
|
|
struct bt1_axi *axi = data;
|
|
|
|
clk_disable_unprepare(axi->aclk);
|
|
}
|
|
|
|
static int bt1_axi_request_clk(struct bt1_axi *axi)
|
|
{
|
|
int ret;
|
|
|
|
axi->aclk = devm_clk_get(axi->dev, "aclk");
|
|
if (IS_ERR(axi->aclk)) {
|
|
dev_err(axi->dev, "Couldn't get AXI Interconnect clock\n");
|
|
return PTR_ERR(axi->aclk);
|
|
}
|
|
|
|
ret = clk_prepare_enable(axi->aclk);
|
|
if (ret) {
|
|
dev_err(axi->dev, "Couldn't enable the AXI clock\n");
|
|
return ret;
|
|
}
|
|
|
|
ret = devm_add_action_or_reset(axi->dev, bt1_axi_disable_clk, axi);
|
|
if (ret)
|
|
dev_err(axi->dev, "Can't add AXI clock disable action\n");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int bt1_axi_request_irq(struct bt1_axi *axi)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(axi->dev);
|
|
int ret;
|
|
|
|
axi->irq = platform_get_irq(pdev, 0);
|
|
if (axi->irq < 0)
|
|
return axi->irq;
|
|
|
|
ret = devm_request_irq(axi->dev, axi->irq, bt1_axi_isr, IRQF_SHARED,
|
|
"bt1-axi", axi);
|
|
if (ret)
|
|
dev_err(axi->dev, "Couldn't request AXI EHB IRQ\n");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t count_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct bt1_axi *axi = dev_get_drvdata(dev);
|
|
|
|
return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&axi->count));
|
|
}
|
|
static DEVICE_ATTR_RO(count);
|
|
|
|
static ssize_t inject_error_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
return scnprintf(buf, PAGE_SIZE, "Error injection: bus unaligned\n");
|
|
}
|
|
|
|
static ssize_t inject_error_store(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *data, size_t count)
|
|
{
|
|
struct bt1_axi *axi = dev_get_drvdata(dev);
|
|
|
|
/*
|
|
* Performing unaligned read from the memory will cause the CM2 bus
|
|
* error while unaligned writing - the AXI bus write error handled
|
|
* by this driver.
|
|
*/
|
|
if (sysfs_streq(data, "bus"))
|
|
readb(axi->qos_regs);
|
|
else if (sysfs_streq(data, "unaligned"))
|
|
writeb(0, axi->qos_regs);
|
|
else
|
|
return -EINVAL;
|
|
|
|
return count;
|
|
}
|
|
static DEVICE_ATTR_RW(inject_error);
|
|
|
|
static struct attribute *bt1_axi_sysfs_attrs[] = {
|
|
&dev_attr_count.attr,
|
|
&dev_attr_inject_error.attr,
|
|
NULL
|
|
};
|
|
ATTRIBUTE_GROUPS(bt1_axi_sysfs);
|
|
|
|
static void bt1_axi_remove_sysfs(void *data)
|
|
{
|
|
struct bt1_axi *axi = data;
|
|
|
|
device_remove_groups(axi->dev, bt1_axi_sysfs_groups);
|
|
}
|
|
|
|
static int bt1_axi_init_sysfs(struct bt1_axi *axi)
|
|
{
|
|
int ret;
|
|
|
|
ret = device_add_groups(axi->dev, bt1_axi_sysfs_groups);
|
|
if (ret) {
|
|
dev_err(axi->dev, "Failed to add sysfs files group\n");
|
|
return ret;
|
|
}
|
|
|
|
ret = devm_add_action_or_reset(axi->dev, bt1_axi_remove_sysfs, axi);
|
|
if (ret)
|
|
dev_err(axi->dev, "Can't add AXI EHB sysfs remove action\n");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int bt1_axi_probe(struct platform_device *pdev)
|
|
{
|
|
struct bt1_axi *axi;
|
|
int ret;
|
|
|
|
axi = bt1_axi_create_data(pdev);
|
|
if (IS_ERR(axi))
|
|
return PTR_ERR(axi);
|
|
|
|
ret = bt1_axi_request_regs(axi);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = bt1_axi_request_rst(axi);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = bt1_axi_request_clk(axi);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = bt1_axi_request_irq(axi);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = bt1_axi_init_sysfs(axi);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id bt1_axi_of_match[] = {
|
|
{ .compatible = "baikal,bt1-axi" },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, bt1_axi_of_match);
|
|
|
|
static struct platform_driver bt1_axi_driver = {
|
|
.probe = bt1_axi_probe,
|
|
.driver = {
|
|
.name = "bt1-axi",
|
|
.of_match_table = bt1_axi_of_match
|
|
}
|
|
};
|
|
module_platform_driver(bt1_axi_driver);
|
|
|
|
MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
|
|
MODULE_DESCRIPTION("Baikal-T1 AXI-bus driver");
|
|
MODULE_LICENSE("GPL v2");
|