[PATCH v5 2/2] clk: add artpec-6 clock controller

From: Lars Persson
Date: Thu Mar 31 2016 - 14:03:28 EST


Add a driver for the main clock controller of the Artpec-6 Soc.

Signed-off-by: Lars Persson <larper@xxxxxxxx>
---
MAINTAINERS | 2 +-
drivers/clk/Makefile | 1 +
drivers/clk/axis/Makefile | 1 +
drivers/clk/axis/clk-artpec6.c | 230 +++++++++++++++++++++++++++++++++++++++++
4 files changed, 233 insertions(+), 1 deletion(-)
create mode 100644 drivers/clk/axis/Makefile
create mode 100644 drivers/clk/axis/clk-artpec6.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 378ebff..074e39e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -973,7 +973,7 @@ S: Maintained
L: linux-arm-kernel@xxxxxxxx
F: arch/arm/mach-artpec
F: arch/arm/boot/dts/artpec6*
-F: drivers/clk/clk-artpec6.c
+F: drivers/clk/axis

ARM/ATMEL AT91RM9200, AT91SAM9 AND SAMA5 SOC SUPPORT
M: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 46869d6..ca9aa7b 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o
obj-$(CONFIG_COMMON_CLK_XGENE) += clk-xgene.o
obj-$(CONFIG_COMMON_CLK_PWM) += clk-pwm.o
obj-$(CONFIG_COMMON_CLK_AT91) += at91/
+obj-$(CONFIG_ARCH_ARTPEC) += axis/
obj-y += bcm/
obj-$(CONFIG_ARCH_BERLIN) += berlin/
obj-$(CONFIG_ARCH_HISI) += hisilicon/
diff --git a/drivers/clk/axis/Makefile b/drivers/clk/axis/Makefile
new file mode 100644
index 0000000..628c9d3
--- /dev/null
+++ b/drivers/clk/axis/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_MACH_ARTPEC6) += clk-artpec6.o
diff --git a/drivers/clk/axis/clk-artpec6.c b/drivers/clk/axis/clk-artpec6.c
new file mode 100644
index 0000000..cf716f1
--- /dev/null
+++ b/drivers/clk/axis/clk-artpec6.c
@@ -0,0 +1,230 @@
+/*
+ * ARTPEC-6 clock initialization
+ *
+ * Copyright 2015-2016 Axis Comunications AB.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <dt-bindings/clock/axis,artpec6-clkctrl.h>
+
+#define NUM_I2S_CLOCKS 2
+
+struct artpec6_clkctrl_drvdata {
+ struct clk *clk_table[ARTPEC6_CLK_NUMCLOCKS];
+ void __iomem *syscon_base;
+ struct clk_onecell_data clk_data;
+ spinlock_t i2scfg_lock;
+};
+
+
+static struct artpec6_clkctrl_drvdata *clkdata;
+
+static const char *i2s_clk_names[NUM_I2S_CLOCKS] = {
+ "i2s0",
+ "i2s1",
+};
+
+static const int i2s_clk_indexes[NUM_I2S_CLOCKS] = {
+ ARTPEC6_CLK_I2S0_CLK,
+ ARTPEC6_CLK_I2S1_CLK,
+};
+
+static void of_artpec6_clkctrl_setup(struct device_node *np)
+{
+ int i;
+ const char *sys_refclk_name;
+ u32 pll_mode, pll_m, pll_n;
+
+ pr_info("of_artpec6_clkctrl_setup\n");
+
+ /* Mandatory parent clock. */
+ i = of_property_match_string(np, "clock-names", "sys_refclk");
+ if (i < 0)
+ return;
+
+ sys_refclk_name = of_clk_get_parent_name(np, i);
+
+ clkdata = kzalloc(sizeof(*clkdata), GFP_KERNEL);
+ if (!clkdata)
+ return;
+
+ for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i)
+ clkdata->clk_table[i] = ERR_PTR(-EPROBE_DEFER);
+
+ clkdata->syscon_base = of_iomap(np, 0);
+
+ /* Read PLL1 factors configured by boot strap pins. */
+ pll_mode = (readl(clkdata->syscon_base) >> 6) & 3;
+ switch (pll_mode) {
+ case 0: /* DDR3-2133 mode */
+ pll_m = 4;
+ pll_n = 85;
+ break;
+ case 1: /* DDR3-1866 mode */
+ pll_m = 6;
+ pll_n = 112;
+ break;
+ case 2: /* DDR3-1600 mode */
+ pll_m = 4;
+ pll_n = 64;
+ break;
+ case 3: /* DDR3-1333 mode */
+ pll_m = 8;
+ pll_n = 106;
+ break;
+ }
+
+ clkdata->clk_table[ARTPEC6_CLK_CPU] =
+ clk_register_fixed_factor(NULL, "cpu", sys_refclk_name, 0, pll_n,
+ pll_m);
+ clkdata->clk_table[ARTPEC6_CLK_CPU_PERIPH] =
+ clk_register_fixed_factor(NULL, "cpu_periph", "cpu", 0, 1, 2);
+
+ /* EPROBE_DEFER on the apb_clock is not handled in amba devices. */
+ clkdata->clk_table[ARTPEC6_CLK_UART_PCLK] =
+ clk_register_fixed_factor(NULL, "uart_pclk", "cpu", 0, 1, 8);
+ clkdata->clk_table[ARTPEC6_CLK_UART_REFCLK] =
+ clk_register_fixed_rate(NULL, "uart_ref", sys_refclk_name, 0,
+ 50000000);
+
+ clkdata->clk_table[ARTPEC6_CLK_SPI_PCLK] =
+ clk_register_fixed_factor(NULL, "spi_pclk", "cpu", 0, 1, 8);
+ clkdata->clk_table[ARTPEC6_CLK_SPI_SSPCLK] =
+ clk_register_fixed_rate(NULL, "spi_sspclk", sys_refclk_name, 0,
+ 50000000);
+
+ clkdata->clk_table[ARTPEC6_CLK_DBG_PCLK] =
+ clk_register_fixed_factor(NULL, "dbg_pclk", "cpu", 0, 1, 8);
+
+ clkdata->clk_data.clks = clkdata->clk_table;
+ clkdata->clk_data.clk_num = ARTPEC6_CLK_NUMCLOCKS;
+
+ of_clk_add_provider(np, of_clk_src_onecell_get, &clkdata->clk_data);
+}
+
+CLK_OF_DECLARE(artpec6_clkctrl, "axis,artpec6-clkctrl",
+ of_artpec6_clkctrl_setup);
+
+static int artpec6_clkctrl_probe(struct platform_device *pdev)
+{
+ int propidx;
+ struct device_node *np = pdev->dev.of_node;
+ const char *sys_refclk_name;
+ const char *i2s_refclk_name = NULL;
+ const char *frac_clk_name[2] = { NULL, NULL };
+ const char *i2s_mux_parents[2] = { NULL, NULL };
+ u32 muxreg;
+ u32 i;
+
+ /* Mandatory parent clock. */
+ propidx = of_property_match_string(np, "clock-names", "sys_refclk");
+ if (propidx < 0)
+ return -EINVAL;
+
+ sys_refclk_name = of_clk_get_parent_name(np, propidx);
+
+ /* Find clock names of optional parent clocks. */
+ propidx = of_property_match_string(np, "clock-names", "i2s_refclk");
+ if (propidx >= 0)
+ i2s_refclk_name = of_clk_get_parent_name(np, propidx);
+
+ propidx = of_property_match_string(np, "clock-names", "frac_clk0");
+ if (propidx >= 0)
+ frac_clk_name[0] = of_clk_get_parent_name(np, propidx);
+ propidx = of_property_match_string(np, "clock-names", "frac_clk1");
+ if (propidx >= 0)
+ frac_clk_name[1] = of_clk_get_parent_name(np, propidx);
+
+ spin_lock_init(&clkdata->i2scfg_lock);
+
+ clkdata->clk_table[ARTPEC6_CLK_NAND_CLKA] =
+ clk_register_fixed_factor(NULL, "nand_clka", "cpu", 0, 1, 8);
+ clkdata->clk_table[ARTPEC6_CLK_NAND_CLKB] =
+ clk_register_fixed_rate(NULL, "nand_clkb", sys_refclk_name, 0,
+ 100000000);
+ clkdata->clk_table[ARTPEC6_CLK_ETH_ACLK] =
+ clk_register_fixed_factor(NULL, "eth_aclk", "cpu", 0, 1, 4);
+ clkdata->clk_table[ARTPEC6_CLK_DMA_ACLK] =
+ clk_register_fixed_factor(NULL, "dma_aclk", "cpu", 0, 1, 4);
+ clkdata->clk_table[ARTPEC6_CLK_PTP_REF] =
+ clk_register_fixed_rate(NULL, "ptp_ref", sys_refclk_name, 0,
+ 100000000);
+ clkdata->clk_table[ARTPEC6_CLK_SD_PCLK] =
+ clk_register_fixed_rate(NULL, "sd_pclk", sys_refclk_name, 0,
+ 100000000);
+ clkdata->clk_table[ARTPEC6_CLK_SD_IMCLK] =
+ clk_register_fixed_rate(NULL, "sd_imclk", sys_refclk_name, 0,
+ 100000000);
+ clkdata->clk_table[ARTPEC6_CLK_I2S_HST] =
+ clk_register_fixed_factor(NULL, "i2s_hst", "cpu", 0, 1, 8);
+
+ for (i = 0; i < NUM_I2S_CLOCKS; ++i) {
+ if (i2s_refclk_name && frac_clk_name[i]) {
+ i2s_mux_parents[0] = frac_clk_name[i];
+ i2s_mux_parents[1] = i2s_refclk_name;
+
+ clkdata->clk_table[i2s_clk_indexes[i]] =
+ clk_register_mux(NULL, i2s_clk_names[i],
+ i2s_mux_parents, 2,
+ CLK_SET_RATE_NO_REPARENT |
+ CLK_SET_RATE_PARENT,
+ clkdata->syscon_base + 0x14, i, 1,
+ 0, &clkdata->i2scfg_lock);
+ } else if (frac_clk_name[i]) {
+ /* Lock the mux for internal clock reference. */
+ muxreg = readl(clkdata->syscon_base + 0x14);
+ muxreg &= ~BIT(i);
+ writel(muxreg, clkdata->syscon_base + 0x14);
+ clkdata->clk_table[i2s_clk_indexes[i]] =
+ clk_register_fixed_factor(NULL, i2s_clk_names[i],
+ frac_clk_name[i], 0, 1,
+ 1);
+ } else if (i2s_refclk_name) {
+ /* Lock the mux for external clock reference. */
+ muxreg = readl(clkdata->syscon_base + 0x14);
+ muxreg |= BIT(i);
+ writel(muxreg, clkdata->syscon_base + 0x14);
+ clkdata->clk_table[i2s_clk_indexes[i]] =
+ clk_register_fixed_factor(NULL, i2s_clk_names[i],
+ i2s_refclk_name, 0, 1, 1);
+ }
+ }
+
+ clkdata->clk_table[ARTPEC6_CLK_I2C] =
+ clk_register_fixed_rate(NULL, "i2c", sys_refclk_name, 0, 100000000);
+
+ clkdata->clk_table[ARTPEC6_CLK_SYS_TIMER] =
+ clk_register_fixed_rate(NULL, "timer", sys_refclk_name, 0,
+ 100000000);
+ clkdata->clk_table[ARTPEC6_CLK_FRACDIV_IN] =
+ clk_register_fixed_rate(NULL, "fracdiv_in", sys_refclk_name, 0,
+ 600000000);
+
+ return 0;
+}
+
+static const struct of_device_id artpec_clkctrl_of_match[] = {
+ { .compatible = "axis,artpec6-clkctrl" },
+ {},
+};
+
+static struct platform_driver artpec6_clkctrl_driver = {
+ .probe = artpec6_clkctrl_probe,
+ .driver = {
+ .name = "artpec6_clkctrl",
+ .of_match_table = artpec_clkctrl_of_match,
+ },
+};
+
+builtin_platform_driver(artpec6_clkctrl_driver);
--
2.1.4