mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-02 07:04:24 +00:00
Code Issues Releases Wiki Activity

cpufreq: imx6q: read OCOTP through nvmem for imx6q

Browse source 
Directly accessing OCOTP registers should be avoided, because
it could not handle OCOTP clks and could not handle defer
proper. With nvmem API, it is safe to access OCOTP registers.

To make sure old dtb could work, the original code still kept.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
This commit is contained in:
Peng Fan 2020-03-03 10:14:50 +08:00 committed by Viresh Kumar
parent 3646f50a38
commit 4bd8459b6c
1 changed files with 38 additions and 29 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

67
drivers/cpufreq/imx6q-cpufreq.c
View file

@ -216,31 +216,41 @@ static struct cpufreq_driver imx6q_cpufreq_driver = {
#define OCOTP_CFG3_SPEED_996MHZ 0x2
#define OCOTP_CFG3_SPEED_852MHZ 0x1
static void imx6q_opp_check_speed_grading(struct device *dev)
static int imx6q_opp_check_speed_grading(struct device *dev)
{
struct device_node *np;
void __iomem *base;
u32 val;
int ret;
np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-ocotp");
if (!np)
return;
if (of_find_property(dev->of_node, "nvmem-cells", NULL)) {
ret = nvmem_cell_read_u32(dev, "speed_grade", &val);
if (ret)
return ret;
} else {
np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-ocotp");
if (!np)
return -ENOENT;
base = of_iomap(np, 0);
if (!base) {
dev_err(dev, "failed to map ocotp\n");
goto put_node;
base = of_iomap(np, 0);
of_node_put(np);
if (!base) {
dev_err(dev, "failed to map ocotp\n");
return -EFAULT;
}
/*
* SPEED_GRADING[1:0] defines the max speed of ARM:
* 2b'11: 1200000000Hz;
* 2b'10: 996000000Hz;
* 2b'01: 852000000Hz; -- i.MX6Q Only, exclusive with 996MHz.
* 2b'00: 792000000Hz;
* We need to set the max speed of ARM according to fuse map.
*/
val = readl_relaxed(base + OCOTP_CFG3);
iounmap(base);
}
/*
* SPEED_GRADING[1:0] defines the max speed of ARM:
* 2b'11: 1200000000Hz;
* 2b'10: 996000000Hz;
* 2b'01: 852000000Hz; -- i.MX6Q Only, exclusive with 996MHz.
* 2b'00: 792000000Hz;
* We need to set the max speed of ARM according to fuse map.
*/
val = readl_relaxed(base + OCOTP_CFG3);
val >>= OCOTP_CFG3_SPEED_SHIFT;
val &= 0x3;
@ -257,9 +267,8 @@ static void imx6q_opp_check_speed_grading(struct device *dev)
if (dev_pm_opp_disable(dev, 1200000000))
dev_warn(dev, "failed to disable 1.2GHz OPP\n");
}
iounmap(base);
put_node:
of_node_put(np);
return 0;
}
#define OCOTP_CFG3_6UL_SPEED_696MHZ 0x2
@ -387,16 +396,16 @@ static int imx6q_cpufreq_probe(struct platform_device *pdev)
if (of_machine_is_compatible("fsl,imx6ul") ||
of_machine_is_compatible("fsl,imx6ull")) {
ret = imx6ul_opp_check_speed_grading(cpu_dev);
if (ret) {
if (ret == -EPROBE_DEFER)
goto out_free_opp;
dev_err(cpu_dev, "failed to read ocotp: %d\n",
ret);
goto out_free_opp;
}
} else {
imx6q_opp_check_speed_grading(cpu_dev);
ret = imx6q_opp_check_speed_grading(cpu_dev);
}
if (ret) {
if (ret == -EPROBE_DEFER)
goto out_free_opp;
dev_err(cpu_dev, "failed to read ocotp: %d\n",
ret);
goto out_free_opp;
}
num = dev_pm_opp_get_opp_count(cpu_dev);