Right now in upstream imx8m cpufreq support just lists a common subset
of OPPs because the higher ones should only be attempted after checking
speed grading in fuses.
Add a small driver which checks speed grading from nvmem cells before
registering cpufreq-dt.
This driver allows unlocking all frequencies for imx8mm and imx8mq and
could be applied to other chips like imx7d
Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
---
drivers/cpufreq/Kconfig.arm | 9 +++
drivers/cpufreq/Makefile | 1 +
drivers/cpufreq/cpufreq-dt-platdev.c | 3 +
drivers/cpufreq/imx-cpufreq-dt.c | 96 ++++++++++++++++++++++++++++
drivers/soc/imx/soc-imx8.c | 3 +
5 files changed, 112 insertions(+)
create mode 100644 drivers/cpufreq/imx-cpufreq-dt.c
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index 179a1d302f48..982efdf9c7e5 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -90,10 +90,19 @@ config ARM_IMX6Q_CPUFREQ
help
This adds cpufreq driver support for Freescale i.MX6 series SoCs.
If in doubt, say N.
+config ARM_IMX_CPUFREQ_DT
+ tristate "Freescale i.MX8M cpufreq support"
+ depends on ARCH_MXC && CPUFREQ_DT
+ help
+ This adds cpufreq driver support for Freescale i.MX8M series SoCs,
+ based on cpufreq-dt.
+
+ If in doubt, say N.
+
config ARM_KIRKWOOD_CPUFREQ
def_bool MACH_KIRKWOOD
help
This adds the CPUFreq driver for Marvell Kirkwood
SoCs.
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index 689b26c6f949..7bcda2273d0c 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -54,10 +54,11 @@ obj-$(CONFIG_ARM_ARMADA_8K_CPUFREQ) += armada-8k-cpufreq.o
obj-$(CONFIG_ARM_BRCMSTB_AVS_CPUFREQ) += brcmstb-avs-cpufreq.o
obj-$(CONFIG_ACPI_CPPC_CPUFREQ) += cppc_cpufreq.o
obj-$(CONFIG_ARCH_DAVINCI) += davinci-cpufreq.o
obj-$(CONFIG_ARM_HIGHBANK_CPUFREQ) += highbank-cpufreq.o
obj-$(CONFIG_ARM_IMX6Q_CPUFREQ) += imx6q-cpufreq.o
+obj-$(CONFIG_ARM_IMX_CPUFREQ_DT) += imx-cpufreq-dt.o
obj-$(CONFIG_ARM_KIRKWOOD_CPUFREQ) += kirkwood-cpufreq.o
obj-$(CONFIG_ARM_MEDIATEK_CPUFREQ) += mediatek-cpufreq.o
obj-$(CONFIG_MACH_MVEBU_V7) += mvebu-cpufreq.o
obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o
obj-$(CONFIG_ARM_PXA2xx_CPUFREQ) += pxa2xx-cpufreq.o
diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c
index 47729a22c159..19c1aad57e26 100644
--- a/drivers/cpufreq/cpufreq-dt-platdev.c
+++ b/drivers/cpufreq/cpufreq-dt-platdev.c
@@ -106,10 +106,13 @@ static const struct of_device_id whitelist[] __initconst = {
*/
static const struct of_device_id blacklist[] __initconst = {
{ .compatible = "calxeda,highbank", },
{ .compatible = "calxeda,ecx-2000", },
+ { .compatible = "fsl,imx8mq", },
+ { .compatible = "fsl,imx8mm", },
+
{ .compatible = "marvell,armadaxp", },
{ .compatible = "mediatek,mt2701", },
{ .compatible = "mediatek,mt2712", },
{ .compatible = "mediatek,mt7622", },
diff --git a/drivers/cpufreq/imx-cpufreq-dt.c b/drivers/cpufreq/imx-cpufreq-dt.c
new file mode 100644
index 000000000000..e1aa346efa10
--- /dev/null
+++ b/drivers/cpufreq/imx-cpufreq-dt.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP
+ */
+
+#include <linux/cpu.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/slab.h>
+
+#define OCOTP_CFG3_SPEED_GRADE_SHIFT 8
+#define OCOTP_CFG3_SPEED_GRADE_MASK (0x3 << 8)
+#define OCOTP_CFG3_MKT_SEGMENT_SHIFT 6
+#define OCOTP_CFG3_MKT_SEGMENT_MASK (0x3 << 6)
+
+static const struct of_device_id imx_cpufreq_dt_match_list[] = {
+ { .compatible = "fsl,imx8mm" },
+ { .compatible = "fsl,imx8mq" },
+ {}
+};
+
+/* cpufreq-dt device registered by imx-cpufreq-dt */
+static struct platform_device *cpufreq_dt_pdev;
+static struct opp_table *cpufreq_opp_table;
+
+static int imx_cpufreq_dt_probe(struct platform_device *pdev)
+{
+ struct device *cpu_dev = get_cpu_device(0);
+ struct device_node *np;
+ const struct of_device_id *match;
+ u32 cell_value, supported_hw[2];
+ int speed_grade, mkt_segment;
+ int ret;
+
+ np = of_find_node_by_path("/");
+ match = of_match_node(imx_cpufreq_dt_match_list, np);
+ of_node_put(np);
+ if (!match)
+ return -ENODEV;
+
+ ret = nvmem_cell_read_u32(cpu_dev, "speed_grade", &cell_value);
+ if (ret)
+ return ret;
+
+ speed_grade = (cell_value & OCOTP_CFG3_SPEED_GRADE_MASK) >> OCOTP_CFG3_SPEED_GRADE_SHIFT;
+ mkt_segment = (cell_value & OCOTP_CFG3_MKT_SEGMENT_MASK) >> OCOTP_CFG3_MKT_SEGMENT_SHIFT;
+ supported_hw[0] = BIT(speed_grade);
+ supported_hw[1] = BIT(mkt_segment);
+ dev_info(&pdev->dev, "cpu speed grade %d mkt segment %d supported-hw %#x %#x\n",
+ speed_grade, mkt_segment, supported_hw[0], supported_hw[1]);
+
+ cpufreq_opp_table = dev_pm_opp_set_supported_hw(cpu_dev, supported_hw, 2);
+ if (IS_ERR(cpufreq_opp_table)) {
+ ret = PTR_ERR(cpufreq_opp_table);
+ dev_err(&pdev->dev, "Failed to set supported opp: %d\n", ret);
+ return ret;
+ }
+
+ cpufreq_dt_pdev = platform_device_register_data(
+ &pdev->dev, "cpufreq-dt", -1, NULL, 0);
+ if (IS_ERR(cpufreq_dt_pdev)) {
+ dev_pm_opp_put_supported_hw(cpufreq_opp_table);
+ ret = PTR_ERR(cpufreq_dt_pdev);
+ dev_err(&pdev->dev, "Failed to register cpufreq-dt: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int imx_cpufreq_dt_remove(struct platform_device *pdev)
+{
+ platform_device_unregister(cpufreq_dt_pdev);
+ dev_pm_opp_put_supported_hw(cpufreq_opp_table);
+
+ return 0;
+}
+
+static struct platform_driver imx_cpufreq_dt_driver = {
+ .probe = imx_cpufreq_dt_probe,
+ .remove = imx_cpufreq_dt_remove,
+ .driver = {
+ .name = "imx-cpufreq-dt",
+ },
+};
+module_platform_driver(imx_cpufreq_dt_driver);
+
+MODULE_ALIAS("platform:imx-cpufreq-dt");
+MODULE_DESCRIPTION("Freescale i.MX cpufreq speed grading driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/soc/imx/soc-imx8.c b/drivers/soc/imx/soc-imx8.c
index cd10726e64e4..02988bdfbb73 100644
--- a/drivers/soc/imx/soc-imx8.c
+++ b/drivers/soc/imx/soc-imx8.c
@@ -130,10 +130,13 @@ static int __init imx8_soc_init(void)
soc_dev = soc_device_register(soc_dev_attr);
if (IS_ERR(soc_dev))
goto free_rev;
+ if (IS_ENABLED(CONFIG_ARM_IMX_CPUFREQ_DT))
+ platform_device_register_simple("imx-cpufreq-dt", -1, NULL, 0);
+
return 0;
free_rev:
kfree(soc_dev_attr->revision);
free_soc:
--
2.17.1
