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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/mips/ar7/clock.c
Initial import
Diffstat (limited to 'arch/mips/ar7/clock.c')
-rw-r--r--arch/mips/ar7/clock.c475
1 files changed, 475 insertions, 0 deletions
diff --git a/arch/mips/ar7/clock.c b/arch/mips/ar7/clock.c
new file mode 100644
index 000000000..2460f9d23
--- /dev/null
+++ b/arch/mips/ar7/clock.c
@@ -0,0 +1,475 @@
+/*
+ * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
+ * Copyright (C) 2009 Florian Fainelli <florian@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/gcd.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+
+#include <asm/addrspace.h>
+#include <asm/mach-ar7/ar7.h>
+
+#define BOOT_PLL_SOURCE_MASK 0x3
+#define CPU_PLL_SOURCE_SHIFT 16
+#define BUS_PLL_SOURCE_SHIFT 14
+#define USB_PLL_SOURCE_SHIFT 18
+#define DSP_PLL_SOURCE_SHIFT 22
+#define BOOT_PLL_SOURCE_AFE 0
+#define BOOT_PLL_SOURCE_BUS 0
+#define BOOT_PLL_SOURCE_REF 1
+#define BOOT_PLL_SOURCE_XTAL 2
+#define BOOT_PLL_SOURCE_CPU 3
+#define BOOT_PLL_BYPASS 0x00000020
+#define BOOT_PLL_ASYNC_MODE 0x02000000
+#define BOOT_PLL_2TO1_MODE 0x00008000
+
+#define TNETD7200_CLOCK_ID_CPU 0
+#define TNETD7200_CLOCK_ID_DSP 1
+#define TNETD7200_CLOCK_ID_USB 2
+
+#define TNETD7200_DEF_CPU_CLK 211000000
+#define TNETD7200_DEF_DSP_CLK 125000000
+#define TNETD7200_DEF_USB_CLK 48000000
+
+struct tnetd7300_clock {
+ u32 ctrl;
+#define PREDIV_MASK 0x001f0000
+#define PREDIV_SHIFT 16
+#define POSTDIV_MASK 0x0000001f
+ u32 unused1[3];
+ u32 pll;
+#define MUL_MASK 0x0000f000
+#define MUL_SHIFT 12
+#define PLL_MODE_MASK 0x00000001
+#define PLL_NDIV 0x00000800
+#define PLL_DIV 0x00000002
+#define PLL_STATUS 0x00000001
+ u32 unused2[3];
+};
+
+struct tnetd7300_clocks {
+ struct tnetd7300_clock bus;
+ struct tnetd7300_clock cpu;
+ struct tnetd7300_clock usb;
+ struct tnetd7300_clock dsp;
+};
+
+struct tnetd7200_clock {
+ u32 ctrl;
+ u32 unused1[3];
+#define DIVISOR_ENABLE_MASK 0x00008000
+ u32 mul;
+ u32 prediv;
+ u32 postdiv;
+ u32 postdiv2;
+ u32 unused2[6];
+ u32 cmd;
+ u32 status;
+ u32 cmden;
+ u32 padding[15];
+};
+
+struct tnetd7200_clocks {
+ struct tnetd7200_clock cpu;
+ struct tnetd7200_clock dsp;
+ struct tnetd7200_clock usb;
+};
+
+static struct clk bus_clk = {
+ .rate = 125000000,
+};
+
+static struct clk cpu_clk = {
+ .rate = 150000000,
+};
+
+static struct clk dsp_clk;
+static struct clk vbus_clk;
+
+static void approximate(int base, int target, int *prediv,
+ int *postdiv, int *mul)
+{
+ int i, j, k, freq, res = target;
+ for (i = 1; i <= 16; i++)
+ for (j = 1; j <= 32; j++)
+ for (k = 1; k <= 32; k++) {
+ freq = abs(base / j * i / k - target);
+ if (freq < res) {
+ res = freq;
+ *mul = i;
+ *prediv = j;
+ *postdiv = k;
+ }
+ }
+}
+
+static void calculate(int base, int target, int *prediv, int *postdiv,
+ int *mul)
+{
+ int tmp_gcd, tmp_base, tmp_freq;
+
+ for (*prediv = 1; *prediv <= 32; (*prediv)++) {
+ tmp_base = base / *prediv;
+ tmp_gcd = gcd(target, tmp_base);
+ *mul = target / tmp_gcd;
+ *postdiv = tmp_base / tmp_gcd;
+ if ((*mul < 1) || (*mul >= 16))
+ continue;
+ if ((*postdiv > 0) & (*postdiv <= 32))
+ break;
+ }
+
+ if (base / *prediv * *mul / *postdiv != target) {
+ approximate(base, target, prediv, postdiv, mul);
+ tmp_freq = base / *prediv * *mul / *postdiv;
+ printk(KERN_WARNING
+ "Adjusted requested frequency %d to %d\n",
+ target, tmp_freq);
+ }
+
+ printk(KERN_DEBUG "Clocks: prediv: %d, postdiv: %d, mul: %d\n",
+ *prediv, *postdiv, *mul);
+}
+
+static int tnetd7300_dsp_clock(void)
+{
+ u32 didr1, didr2;
+ u8 rev = ar7_chip_rev();
+ didr1 = readl((void *)KSEG1ADDR(AR7_REGS_GPIO + 0x18));
+ didr2 = readl((void *)KSEG1ADDR(AR7_REGS_GPIO + 0x1c));
+ if (didr2 & (1 << 23))
+ return 0;
+ if ((rev >= 0x23) && (rev != 0x57))
+ return 250000000;
+ if ((((didr2 & 0x1fff) << 10) | ((didr1 & 0xffc00000) >> 22))
+ > 4208000)
+ return 250000000;
+ return 0;
+}
+
+static int tnetd7300_get_clock(u32 shift, struct tnetd7300_clock *clock,
+ u32 *bootcr, u32 bus_clock)
+{
+ int product;
+ int base_clock = AR7_REF_CLOCK;
+ u32 ctrl = readl(&clock->ctrl);
+ u32 pll = readl(&clock->pll);
+ int prediv = ((ctrl & PREDIV_MASK) >> PREDIV_SHIFT) + 1;
+ int postdiv = (ctrl & POSTDIV_MASK) + 1;
+ int divisor = prediv * postdiv;
+ int mul = ((pll & MUL_MASK) >> MUL_SHIFT) + 1;
+
+ switch ((*bootcr & (BOOT_PLL_SOURCE_MASK << shift)) >> shift) {
+ case BOOT_PLL_SOURCE_BUS:
+ base_clock = bus_clock;
+ break;
+ case BOOT_PLL_SOURCE_REF:
+ base_clock = AR7_REF_CLOCK;
+ break;
+ case BOOT_PLL_SOURCE_XTAL:
+ base_clock = AR7_XTAL_CLOCK;
+ break;
+ case BOOT_PLL_SOURCE_CPU:
+ base_clock = cpu_clk.rate;
+ break;
+ }
+
+ if (*bootcr & BOOT_PLL_BYPASS)
+ return base_clock / divisor;
+
+ if ((pll & PLL_MODE_MASK) == 0)
+ return (base_clock >> (mul / 16 + 1)) / divisor;
+
+ if ((pll & (PLL_NDIV | PLL_DIV)) == (PLL_NDIV | PLL_DIV)) {
+ product = (mul & 1) ?
+ (base_clock * mul) >> 1 :
+ (base_clock * (mul - 1)) >> 2;
+ return product / divisor;
+ }
+
+ if (mul == 16)
+ return base_clock / divisor;
+
+ return base_clock * mul / divisor;
+}
+
+static void tnetd7300_set_clock(u32 shift, struct tnetd7300_clock *clock,
+ u32 *bootcr, u32 frequency)
+{
+ int prediv, postdiv, mul;
+ int base_clock = bus_clk.rate;
+
+ switch ((*bootcr & (BOOT_PLL_SOURCE_MASK << shift)) >> shift) {
+ case BOOT_PLL_SOURCE_BUS:
+ base_clock = bus_clk.rate;
+ break;
+ case BOOT_PLL_SOURCE_REF:
+ base_clock = AR7_REF_CLOCK;
+ break;
+ case BOOT_PLL_SOURCE_XTAL:
+ base_clock = AR7_XTAL_CLOCK;
+ break;
+ case BOOT_PLL_SOURCE_CPU:
+ base_clock = cpu_clk.rate;
+ break;
+ }
+
+ calculate(base_clock, frequency, &prediv, &postdiv, &mul);
+
+ writel(((prediv - 1) << PREDIV_SHIFT) | (postdiv - 1), &clock->ctrl);
+ mdelay(1);
+ writel(4, &clock->pll);
+ while (readl(&clock->pll) & PLL_STATUS)
+ ;
+ writel(((mul - 1) << MUL_SHIFT) | (0xff << 3) | 0x0e, &clock->pll);
+ mdelay(75);
+}
+
+static void __init tnetd7300_init_clocks(void)
+{
+ u32 *bootcr = (u32 *)ioremap_nocache(AR7_REGS_DCL, 4);
+ struct tnetd7300_clocks *clocks =
+ ioremap_nocache(UR8_REGS_CLOCKS,
+ sizeof(struct tnetd7300_clocks));
+
+ bus_clk.rate = tnetd7300_get_clock(BUS_PLL_SOURCE_SHIFT,
+ &clocks->bus, bootcr, AR7_AFE_CLOCK);
+
+ if (*bootcr & BOOT_PLL_ASYNC_MODE)
+ cpu_clk.rate = tnetd7300_get_clock(CPU_PLL_SOURCE_SHIFT,
+ &clocks->cpu, bootcr, AR7_AFE_CLOCK);
+ else
+ cpu_clk.rate = bus_clk.rate;
+
+ if (dsp_clk.rate == 250000000)
+ tnetd7300_set_clock(DSP_PLL_SOURCE_SHIFT, &clocks->dsp,
+ bootcr, dsp_clk.rate);
+
+ iounmap(clocks);
+ iounmap(bootcr);
+}
+
+static void tnetd7200_set_clock(int base, struct tnetd7200_clock *clock,
+ int prediv, int postdiv, int postdiv2, int mul, u32 frequency)
+{
+ printk(KERN_INFO
+ "Clocks: base = %d, frequency = %u, prediv = %d, "
+ "postdiv = %d, postdiv2 = %d, mul = %d\n",
+ base, frequency, prediv, postdiv, postdiv2, mul);
+
+ writel(0, &clock->ctrl);
+ writel(DIVISOR_ENABLE_MASK | ((prediv - 1) & 0x1F), &clock->prediv);
+ writel((mul - 1) & 0xF, &clock->mul);
+
+ while (readl(&clock->status) & 0x1)
+ ; /* nop */
+
+ writel(DIVISOR_ENABLE_MASK | ((postdiv - 1) & 0x1F), &clock->postdiv);
+
+ writel(readl(&clock->cmden) | 1, &clock->cmden);
+ writel(readl(&clock->cmd) | 1, &clock->cmd);
+
+ while (readl(&clock->status) & 0x1)
+ ; /* nop */
+
+ writel(DIVISOR_ENABLE_MASK | ((postdiv2 - 1) & 0x1F), &clock->postdiv2);
+
+ writel(readl(&clock->cmden) | 1, &clock->cmden);
+ writel(readl(&clock->cmd) | 1, &clock->cmd);
+
+ while (readl(&clock->status) & 0x1)
+ ; /* nop */
+
+ writel(readl(&clock->ctrl) | 1, &clock->ctrl);
+}
+
+static int tnetd7200_get_clock_base(int clock_id, u32 *bootcr)
+{
+ if (*bootcr & BOOT_PLL_ASYNC_MODE)
+ /* Async */
+ switch (clock_id) {
+ case TNETD7200_CLOCK_ID_DSP:
+ return AR7_REF_CLOCK;
+ default:
+ return AR7_AFE_CLOCK;
+ }
+ else
+ /* Sync */
+ if (*bootcr & BOOT_PLL_2TO1_MODE)
+ /* 2:1 */
+ switch (clock_id) {
+ case TNETD7200_CLOCK_ID_DSP:
+ return AR7_REF_CLOCK;
+ default:
+ return AR7_AFE_CLOCK;
+ }
+ else
+ /* 1:1 */
+ return AR7_REF_CLOCK;
+}
+
+
+static void __init tnetd7200_init_clocks(void)
+{
+ u32 *bootcr = (u32 *)ioremap_nocache(AR7_REGS_DCL, 4);
+ struct tnetd7200_clocks *clocks =
+ ioremap_nocache(AR7_REGS_CLOCKS,
+ sizeof(struct tnetd7200_clocks));
+ int cpu_base, cpu_mul, cpu_prediv, cpu_postdiv;
+ int dsp_base, dsp_mul, dsp_prediv, dsp_postdiv;
+ int usb_base, usb_mul, usb_prediv, usb_postdiv;
+
+ cpu_base = tnetd7200_get_clock_base(TNETD7200_CLOCK_ID_CPU, bootcr);
+ dsp_base = tnetd7200_get_clock_base(TNETD7200_CLOCK_ID_DSP, bootcr);
+
+ if (*bootcr & BOOT_PLL_ASYNC_MODE) {
+ printk(KERN_INFO "Clocks: Async mode\n");
+
+ printk(KERN_INFO "Clocks: Setting DSP clock\n");
+ calculate(dsp_base, TNETD7200_DEF_DSP_CLK,
+ &dsp_prediv, &dsp_postdiv, &dsp_mul);
+ bus_clk.rate =
+ ((dsp_base / dsp_prediv) * dsp_mul) / dsp_postdiv;
+ tnetd7200_set_clock(dsp_base, &clocks->dsp,
+ dsp_prediv, dsp_postdiv * 2, dsp_postdiv, dsp_mul * 2,
+ bus_clk.rate);
+
+ printk(KERN_INFO "Clocks: Setting CPU clock\n");
+ calculate(cpu_base, TNETD7200_DEF_CPU_CLK, &cpu_prediv,
+ &cpu_postdiv, &cpu_mul);
+ cpu_clk.rate =
+ ((cpu_base / cpu_prediv) * cpu_mul) / cpu_postdiv;
+ tnetd7200_set_clock(cpu_base, &clocks->cpu,
+ cpu_prediv, cpu_postdiv, -1, cpu_mul,
+ cpu_clk.rate);
+
+ } else
+ if (*bootcr & BOOT_PLL_2TO1_MODE) {
+ printk(KERN_INFO "Clocks: Sync 2:1 mode\n");
+
+ printk(KERN_INFO "Clocks: Setting CPU clock\n");
+ calculate(cpu_base, TNETD7200_DEF_CPU_CLK, &cpu_prediv,
+ &cpu_postdiv, &cpu_mul);
+ cpu_clk.rate = ((cpu_base / cpu_prediv) * cpu_mul)
+ / cpu_postdiv;
+ tnetd7200_set_clock(cpu_base, &clocks->cpu,
+ cpu_prediv, cpu_postdiv, -1, cpu_mul,
+ cpu_clk.rate);
+
+ printk(KERN_INFO "Clocks: Setting DSP clock\n");
+ calculate(dsp_base, TNETD7200_DEF_DSP_CLK, &dsp_prediv,
+ &dsp_postdiv, &dsp_mul);
+ bus_clk.rate = cpu_clk.rate / 2;
+ tnetd7200_set_clock(dsp_base, &clocks->dsp,
+ dsp_prediv, dsp_postdiv * 2, dsp_postdiv,
+ dsp_mul * 2, bus_clk.rate);
+ } else {
+ printk(KERN_INFO "Clocks: Sync 1:1 mode\n");
+
+ printk(KERN_INFO "Clocks: Setting DSP clock\n");
+ calculate(dsp_base, TNETD7200_DEF_DSP_CLK, &dsp_prediv,
+ &dsp_postdiv, &dsp_mul);
+ bus_clk.rate = ((dsp_base / dsp_prediv) * dsp_mul)
+ / dsp_postdiv;
+ tnetd7200_set_clock(dsp_base, &clocks->dsp,
+ dsp_prediv, dsp_postdiv * 2, dsp_postdiv,
+ dsp_mul * 2, bus_clk.rate);
+
+ cpu_clk.rate = bus_clk.rate;
+ }
+
+ printk(KERN_INFO "Clocks: Setting USB clock\n");
+ usb_base = bus_clk.rate;
+ calculate(usb_base, TNETD7200_DEF_USB_CLK, &usb_prediv,
+ &usb_postdiv, &usb_mul);
+ tnetd7200_set_clock(usb_base, &clocks->usb,
+ usb_prediv, usb_postdiv, -1, usb_mul,
+ TNETD7200_DEF_USB_CLK);
+
+ dsp_clk.rate = cpu_clk.rate;
+
+ iounmap(clocks);
+ iounmap(bootcr);
+}
+
+/*
+ * Linux clock API
+ */
+int clk_enable(struct clk *clk)
+{
+ return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ return clk->rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+struct clk *clk_get(struct device *dev, const char *id)
+{
+ if (!strcmp(id, "bus"))
+ return &bus_clk;
+ /* cpmac and vbus share the same rate */
+ if (!strcmp(id, "cpmac"))
+ return &vbus_clk;
+ if (!strcmp(id, "cpu"))
+ return &cpu_clk;
+ if (!strcmp(id, "dsp"))
+ return &dsp_clk;
+ if (!strcmp(id, "vbus"))
+ return &vbus_clk;
+ return ERR_PTR(-ENOENT);
+}
+EXPORT_SYMBOL(clk_get);
+
+void clk_put(struct clk *clk)
+{
+}
+EXPORT_SYMBOL(clk_put);
+
+void __init ar7_init_clocks(void)
+{
+ switch (ar7_chip_id()) {
+ case AR7_CHIP_7100:
+ case AR7_CHIP_7200:
+ tnetd7200_init_clocks();
+ break;
+ case AR7_CHIP_7300:
+ dsp_clk.rate = tnetd7300_dsp_clock();
+ tnetd7300_init_clocks();
+ break;
+ default:
+ break;
+ }
+ /* adjust vbus clock rate */
+ vbus_clk.rate = bus_clk.rate / 2;
+}