[PATCH v2 2/3] soc: amlogic: Add Meson GX Clock Measure driver
From: Neil Armstrong
Date: Wed Nov 14 2018 - 08:16:42 EST
The Amlogic Meson GX SoCs embeds a clock measurer IP to measure the internal
clock paths frequencies.
The precision is determined by stepping into the divider until the counter
overflows.
The debugfs slows a pretty summary and each clock can be measured
individually aswell.
The clock table covers all GX SoCs (GXBB, GXL & GXM) even if some clocks
are only present on GXBB or GXM (i.e. wave420l) but the counter returns
0 when the clocks are invalid.
Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
drivers/soc/amlogic/Kconfig | 8 +
drivers/soc/amlogic/Makefile | 1 +
drivers/soc/amlogic/meson-gx-clk-measure.c | 293 +++++++++++++++++++++
3 files changed, 302 insertions(+)
create mode 100644 drivers/soc/amlogic/meson-gx-clk-measure.c
diff --git a/drivers/soc/amlogic/Kconfig b/drivers/soc/amlogic/Kconfig
index 2f282b472912..155868830773 100644
--- a/drivers/soc/amlogic/Kconfig
+++ b/drivers/soc/amlogic/Kconfig
@@ -7,6 +7,14 @@ config MESON_CANVAS
help
Say yes to support the canvas IP for Amlogic SoCs.
+config MESON_GX_CLK_MEASURE
+ bool "Amlogic Meson GX SoC Clock Measure driver"
+ depends on ARCH_MESON || COMPILE_TEST
+ default ARCH_MESON
+ help
+ Say yes to support of Measuring a set of internal SoC clocks
+ from the debugfs interface.
+
config MESON_GX_SOCINFO
bool "Amlogic Meson GX SoC Information driver"
depends on ARCH_MESON || COMPILE_TEST
diff --git a/drivers/soc/amlogic/Makefile b/drivers/soc/amlogic/Makefile
index 0ab16d35ac36..2cc0f9c2f715 100644
--- a/drivers/soc/amlogic/Makefile
+++ b/drivers/soc/amlogic/Makefile
@@ -1,4 +1,5 @@
obj-$(CONFIG_MESON_CANVAS) += meson-canvas.o
+obj-$(CONFIG_MESON_GX_CLK_MEASURE) += meson-gx-clk-measure.o
obj-$(CONFIG_MESON_GX_SOCINFO) += meson-gx-socinfo.o
obj-$(CONFIG_MESON_GX_PM_DOMAINS) += meson-gx-pwrc-vpu.o
obj-$(CONFIG_MESON_MX_SOCINFO) += meson-mx-socinfo.o
diff --git a/drivers/soc/amlogic/meson-gx-clk-measure.c b/drivers/soc/amlogic/meson-gx-clk-measure.c
new file mode 100644
index 000000000000..da1a0001cef9
--- /dev/null
+++ b/drivers/soc/amlogic/meson-gx-clk-measure.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2017 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
+ */
+
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/bitfield.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/regmap.h>
+
+#define MSR_CLK_DUTY 0x0
+#define MSR_CLK_REG0 0x4
+#define MSR_CLK_REG1 0x8
+#define MSR_CLK_REG2 0xc
+
+#define MSR_CLK_DIV GENMASK(15, 0)
+#define MSR_ENABLE BIT(16)
+#define MSR_CONT BIT(17) /* continuous measurement */
+#define MSR_INTR BIT(18) /* interrupts */
+#define MSR_RUN BIT(19)
+#define MSR_CLK_SRC GENMASK(26, 20)
+#define MSR_BUSY BIT(31)
+
+#define MSR_VAL_MASK GENMASK(15, 0)
+
+#define DIV_MIN 32
+#define DIV_STEP 32
+#define DIV_MAX 640
+
+#define CLK_MSR_MAX 128
+
+struct meson_gx_msr_id {
+ struct meson_gx_msr *priv;
+ unsigned int id;
+ const char *name;
+};
+
+struct meson_gx_msr {
+ struct regmap *regmap;
+ struct meson_gx_msr_id msr_table[CLK_MSR_MAX];
+};
+
+#define CLK_MSR_ID(__id, __name) \
+ [__id] = {.id = __id, .name = __name,}
+
+static struct meson_gx_msr_id clk_msr_gx[CLK_MSR_MAX] = {
+ CLK_MSR_ID(0, "ring_osc_out_ee_0"),
+ CLK_MSR_ID(1, "ring_osc_out_ee_1"),
+ CLK_MSR_ID(2, "ring_osc_out_ee_2"),
+ CLK_MSR_ID(3, "a53_ring_osc"),
+ CLK_MSR_ID(4, "gp0_pll"),
+ CLK_MSR_ID(6, "enci"),
+ CLK_MSR_ID(7, "clk81"),
+ CLK_MSR_ID(8, "encp"),
+ CLK_MSR_ID(9, "encl"),
+ CLK_MSR_ID(10, "vdac"),
+ CLK_MSR_ID(11, "rgmii_tx"),
+ CLK_MSR_ID(12, "pdm"),
+ CLK_MSR_ID(13, "amclk"),
+ CLK_MSR_ID(14, "fec_0"),
+ CLK_MSR_ID(15, "fec_1"),
+ CLK_MSR_ID(16, "fec_2"),
+ CLK_MSR_ID(17, "sys_pll_div16"),
+ CLK_MSR_ID(18, "sys_cpu_div16"),
+ CLK_MSR_ID(19, "hdmitx_sys"),
+ CLK_MSR_ID(20, "rtc_osc_out"),
+ CLK_MSR_ID(21, "i2s_in_src0"),
+ CLK_MSR_ID(22, "eth_phy_ref"),
+ CLK_MSR_ID(23, "hdmi_todig"),
+ CLK_MSR_ID(26, "sc_int"),
+ CLK_MSR_ID(28, "sar_adc"),
+ CLK_MSR_ID(31, "mpll_test_out"),
+ CLK_MSR_ID(32, "vdec"),
+ CLK_MSR_ID(35, "mali"),
+ CLK_MSR_ID(36, "hdmi_tx_pixel"),
+ CLK_MSR_ID(37, "i958"),
+ CLK_MSR_ID(38, "vdin_meas"),
+ CLK_MSR_ID(39, "pcm_sclk"),
+ CLK_MSR_ID(40, "pcm_mclk"),
+ CLK_MSR_ID(41, "eth_rx_or_rmii"),
+ CLK_MSR_ID(42, "mp0_out"),
+ CLK_MSR_ID(43, "fclk_div5"),
+ CLK_MSR_ID(44, "pwm_b"),
+ CLK_MSR_ID(45, "pwm_a"),
+ CLK_MSR_ID(46, "vpu"),
+ CLK_MSR_ID(47, "ddr_dpll_pt"),
+ CLK_MSR_ID(48, "mp1_out"),
+ CLK_MSR_ID(49, "mp2_out"),
+ CLK_MSR_ID(50, "mp3_out"),
+ CLK_MSR_ID(51, "nand_core"),
+ CLK_MSR_ID(52, "sd_emmc_b"),
+ CLK_MSR_ID(53, "sd_emmc_a"),
+ CLK_MSR_ID(55, "vid_pll_div_out"),
+ CLK_MSR_ID(56, "cci"),
+ CLK_MSR_ID(57, "wave420l_c"),
+ CLK_MSR_ID(58, "wave420l_b"),
+ CLK_MSR_ID(59, "hcodec"),
+ CLK_MSR_ID(60, "alt_32k"),
+ CLK_MSR_ID(61, "gpio_msr"),
+ CLK_MSR_ID(62, "hevc"),
+ CLK_MSR_ID(66, "vid_lock"),
+ CLK_MSR_ID(70, "pwm_f"),
+ CLK_MSR_ID(71, "pwm_e"),
+ CLK_MSR_ID(72, "pwm_d"),
+ CLK_MSR_ID(73, "pwm_c"),
+ CLK_MSR_ID(75, "aoclkx2_int"),
+ CLK_MSR_ID(76, "aoclk_int"),
+ CLK_MSR_ID(77, "rng_ring_osc_0"),
+ CLK_MSR_ID(78, "rng_ring_osc_1"),
+ CLK_MSR_ID(79, "rng_ring_osc_2"),
+ CLK_MSR_ID(80, "rng_ring_osc_3"),
+ CLK_MSR_ID(81, "vapb"),
+ CLK_MSR_ID(82, "ge2d"),
+};
+
+static int meson_gx_measure_id(struct meson_gx_msr_id *clk_msr_id,
+ unsigned int divider)
+{
+ struct meson_gx_msr *priv = clk_msr_id->priv;
+ unsigned int val;
+ int ret;
+
+ regmap_write(priv->regmap, MSR_CLK_REG0, 0);
+
+ /* Set measurement divider */
+ regmap_update_bits(priv->regmap, MSR_CLK_REG0, MSR_CLK_DIV,
+ FIELD_PREP(MSR_CLK_DIV, divider - 1));
+
+ /* Set ID */
+ regmap_update_bits(priv->regmap, MSR_CLK_REG0, MSR_CLK_SRC,
+ FIELD_PREP(MSR_CLK_SRC, clk_msr_id->id));
+
+ /* Enable & Start */
+ regmap_update_bits(priv->regmap, MSR_CLK_REG0,
+ MSR_RUN | MSR_ENABLE,
+ MSR_RUN | MSR_ENABLE);
+
+ ret = regmap_read_poll_timeout(priv->regmap, MSR_CLK_REG0,
+ val, !(val & MSR_BUSY), 10, 10000);
+ if (ret)
+ return ret;
+
+ /* Disable */
+ regmap_update_bits(priv->regmap, MSR_CLK_REG0, MSR_ENABLE, 0);
+
+ /* Get the value in multiple of gate time counts */
+ regmap_read(priv->regmap, MSR_CLK_REG2, &val);
+
+ if (val >= MSR_VAL_MASK)
+ return -EINVAL;
+
+ return DIV_ROUND_CLOSEST((val & MSR_VAL_MASK) * 1000000,
+ divider);
+}
+
+static int meson_gx_measure_best_id(struct meson_gx_msr_id *clk_msr_id,
+ unsigned int *precision)
+{
+ unsigned int divider = DIV_MAX;
+ int ret;
+
+ /* Start from max divider and down to min divider */
+ do {
+ ret = meson_gx_measure_id(clk_msr_id, divider);
+ if (ret >= 0)
+ *precision = (2 * 1000000) / divider;
+ else
+ divider -= DIV_STEP;
+ } while (divider >= DIV_MIN && ret == -EINVAL);
+
+ return ret;
+}
+
+static int clk_msr_show(struct seq_file *s, void *data)
+{
+ struct meson_gx_msr_id *clk_msr_id = s->private;
+ unsigned int precision = 0;
+ int val;
+
+ val = meson_gx_measure_best_id(clk_msr_id, &precision);
+ if (val < 0)
+ return val;
+
+ seq_printf(s, "%d\t+/-%dHz\n", val, precision);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_msr);
+
+static int clk_msr_summary_show(struct seq_file *s, void *data)
+{
+ struct meson_gx_msr_id *msr_table = s->private;
+ unsigned int precision = 0;
+ int val, i;
+
+ seq_puts(s, " clock rate precision\n");
+ seq_puts(s, "---------------------------------------------\n");
+
+ for (i = 0 ; i < CLK_MSR_MAX ; ++i) {
+ if (!msr_table[i].name)
+ continue;
+
+ val = meson_gx_measure_best_id(&msr_table[i], &precision);
+ if (val < 0)
+ return val;
+
+ seq_printf(s, " %-20s %10d +/-%dHz\n",
+ msr_table[i].name, val, precision);
+ }
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_msr_summary);
+
+static const struct regmap_config clk_msr_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = MSR_CLK_REG2,
+};
+
+static int meson_gx_msr_probe(struct platform_device *pdev)
+{
+ const struct meson_gx_msr_id *match_data;
+ struct meson_gx_msr *priv;
+ struct resource *res;
+ struct dentry *root, *clks;
+ void __iomem *base;
+ int i;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(struct meson_gx_msr),
+ GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ match_data = device_get_match_data(&pdev->dev);
+ if (!match_data) {
+ dev_err(&pdev->dev, "failed to get match data\n");
+ return -ENODEV;
+ }
+
+ memcpy(priv->msr_table, match_data, sizeof(priv->msr_table));
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base)) {
+ dev_err(&pdev->dev, "io resource mapping failed\n");
+ return PTR_ERR(base);
+ }
+
+ priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+ &clk_msr_regmap_config);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ root = debugfs_create_dir("meson-clk-msr", NULL);
+ clks = debugfs_create_dir("clks", root);
+
+ debugfs_create_file("measure_summary", 0444, root,
+ priv->msr_table, &clk_msr_summary_fops);
+
+ for (i = 0 ; i < CLK_MSR_MAX ; ++i) {
+ if (!priv->msr_table[i].name)
+ continue;
+
+ priv->msr_table[i].priv = priv;
+
+ debugfs_create_file(priv->msr_table[i].name, 0444, clks,
+ &priv->msr_table[i], &clk_msr_fops);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id meson_gx_msr_match_table[] = {
+ {
+ .compatible = "amlogic,meson-gx-clk-measure",
+ .data = (void *)clk_msr_gx,
+ },
+ { /* sentinel */ }
+};
+
+static struct platform_driver meson_gx_msr_driver = {
+ .probe = meson_gx_msr_probe,
+ .driver = {
+ .name = "meson_gx_msr",
+ .of_match_table = meson_gx_msr_match_table,
+ },
+};
+builtin_platform_driver(meson_gx_msr_driver);
--
2.19.1