[U-Boot] [PATCH atmel/next 1/7] arm920t/at91: add clock.c
Andreas Bießmann
andreas.devel at googlemail.com
Sun Jun 12 13:49:11 CEST 2011
This patch adds an copy of arm926ejs/at91/clock.c to arm920t/at91. The
arm926ejs specialities are removed from arm920t version and vice versa.
Signed-off-by: Andreas Bießmann <andreas.devel at googlemail.com>
---
arch/arm/cpu/arm920t/at91/Makefile | 1 +
arch/arm/cpu/arm920t/at91/clock.c | 160 ++++++++++++++++++++++++++++++++++
arch/arm/cpu/arm926ejs/at91/clock.c | 35 +-------
arch/arm/include/asm/arch-at91/clk.h | 42 ++++++++--
4 files changed, 198 insertions(+), 40 deletions(-)
create mode 100644 arch/arm/cpu/arm920t/at91/clock.c
diff --git a/arch/arm/cpu/arm920t/at91/Makefile b/arch/arm/cpu/arm920t/at91/Makefile
index 5c71b77..8258ecd 100644
--- a/arch/arm/cpu/arm920t/at91/Makefile
+++ b/arch/arm/cpu/arm920t/at91/Makefile
@@ -28,6 +28,7 @@ LIB = $(obj)lib$(SOC).o
SOBJS += lowlevel_init.o
COBJS += reset.o
COBJS += timer.o
+COBJS += clock.o
SRCS := $(SOBJS:.o=.S) $(COBJS:.o=.c)
OBJS := $(addprefix $(obj),$(SOBJS) $(COBJS))
diff --git a/arch/arm/cpu/arm920t/at91/clock.c b/arch/arm/cpu/arm920t/at91/clock.c
new file mode 100644
index 0000000..02318b3
--- /dev/null
+++ b/arch/arm/cpu/arm920t/at91/clock.c
@@ -0,0 +1,160 @@
+/*
+ * [origin: Linux kernel linux/arch/arm/mach-at91/clock.c]
+ *
+ * Copyright (C) 2011 Andreas Bießmann
+ * Copyright (C) 2005 David Brownell
+ * Copyright (C) 2005 Ivan Kokshaysky
+ * Copyright (C) 2009 Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
+ *
+ * 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.
+ */
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_pmc.h>
+#include <asm/arch/clk.h>
+
+#if !defined(CONFIG_AT91FAMILY)
+# error You need to define CONFIG_AT91FAMILY in your board config!
+#endif
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static unsigned long at91_css_to_rate(unsigned long css)
+{
+ switch (css) {
+ case AT91_PMC_MCKR_CSS_SLOW:
+ return CONFIG_SYS_AT91_SLOW_CLOCK;
+ case AT91_PMC_MCKR_CSS_MAIN:
+ return gd->main_clk_rate_hz;
+ case AT91_PMC_MCKR_CSS_PLLA:
+ return gd->plla_rate_hz;
+ case AT91_PMC_MCKR_CSS_PLLB:
+ return gd->pllb_rate_hz;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_USB_ATMEL
+static unsigned at91_pll_calc(unsigned main_freq, unsigned out_freq)
+{
+ unsigned i, div = 0, mul = 0, diff = 1 << 30;
+ unsigned ret = (out_freq > 155000000) ? 0xbe00 : 0x3e00;
+
+ /* PLL output max 240 MHz (or 180 MHz per errata) */
+ if (out_freq > 240000000)
+ goto fail;
+
+ for (i = 1; i < 256; i++) {
+ int diff1;
+ unsigned input, mul1;
+
+ /*
+ * PLL input between 1MHz and 32MHz per spec, but lower
+ * frequences seem necessary in some cases so allow 100K.
+ * Warning: some newer products need 2MHz min.
+ */
+ input = main_freq / i;
+ if (input < 100000)
+ continue;
+ if (input > 32000000)
+ continue;
+
+ mul1 = out_freq / input;
+ if (mul1 > 2048)
+ continue;
+ if (mul1 < 2)
+ goto fail;
+
+ diff1 = out_freq - input * mul1;
+ if (diff1 < 0)
+ diff1 = -diff1;
+ if (diff > diff1) {
+ diff = diff1;
+ div = i;
+ mul = mul1;
+ if (diff == 0)
+ break;
+ }
+ }
+ if (i == 256 && diff > (out_freq >> 5))
+ goto fail;
+ return ret | ((mul - 1) << 16) | div;
+fail:
+ return 0;
+}
+#endif
+
+static u32 at91_pll_rate(u32 freq, u32 reg)
+{
+ unsigned mul, div;
+
+ div = reg & 0xff;
+ mul = (reg >> 16) & 0x7ff;
+ if (div && mul) {
+ freq /= div;
+ freq *= mul + 1;
+ } else
+ freq = 0;
+
+ return freq;
+}
+
+
+int at91_clock_init(unsigned long main_clock)
+{
+ unsigned freq, mckr;
+ at91_pmc_t *pmc = (at91_pmc_t *) ATMEL_BASE_PMC;
+#ifndef CONFIG_SYS_AT91_MAIN_CLOCK
+ unsigned tmp;
+ /*
+ * When the bootloader initialized the main oscillator correctly,
+ * there's no problem using the cycle counter. But if it didn't,
+ * or when using oscillator bypass mode, we must be told the speed
+ * of the main clock.
+ */
+ if (!main_clock) {
+ do {
+ tmp = readl(&pmc->mcfr);
+ } while (!(tmp & AT91_PMC_MCFR_MAINRDY));
+ tmp &= AT91_PMC_MCFR_MAINF_MASK;
+ main_clock = tmp * (CONFIG_SYS_AT91_SLOW_CLOCK / 16);
+ }
+#endif
+ gd->main_clk_rate_hz = main_clock;
+
+ /* report if PLLA is more than mildly overclocked */
+ gd->plla_rate_hz = at91_pll_rate(main_clock, readl(&pmc->pllar));
+
+#ifdef CONFIG_USB_ATMEL
+ /*
+ * USB clock init: choose 48 MHz PLLB value,
+ * disable 48MHz clock during usb peripheral suspend.
+ *
+ * REVISIT: assumes MCK doesn't derive from PLLB!
+ */
+ gd->at91_pllb_usb_init = at91_pll_calc(main_clock, 48000000 * 2) |
+ AT91_PMC_PLLBR_USBDIV_2;
+ gd->pllb_rate_hz = at91_pll_rate(main_clock, gd->at91_pllb_usb_init);
+#endif
+
+ /*
+ * MCK and CPU derive from one of those primary clocks.
+ * For now, assume this parentage won't change.
+ */
+ mckr = readl(&pmc->mckr);
+ gd->mck_rate_hz = at91_css_to_rate(mckr & AT91_PMC_MCKR_CSS_MASK);
+ freq = gd->mck_rate_hz;
+
+ freq /= (1 << ((mckr & AT91_PMC_MCKR_PRES_MASK) >> 2)); /* prescale */
+ /* mdiv */
+ gd->mck_rate_hz = freq / (1 + ((mckr & AT91_PMC_MCKR_MDIV_MASK) >> 8));
+ gd->cpu_clk_rate_hz = freq;
+
+ return 0;
+}
+
diff --git a/arch/arm/cpu/arm926ejs/at91/clock.c b/arch/arm/cpu/arm926ejs/at91/clock.c
index 608af2c..a7085de 100644
--- a/arch/arm/cpu/arm926ejs/at91/clock.c
+++ b/arch/arm/cpu/arm926ejs/at91/clock.c
@@ -23,36 +23,6 @@
DECLARE_GLOBAL_DATA_PTR;
-unsigned long get_cpu_clk_rate(void)
-{
- return gd->cpu_clk_rate_hz;
-}
-
-unsigned long get_main_clk_rate(void)
-{
- return gd->main_clk_rate_hz;
-}
-
-unsigned long get_mck_clk_rate(void)
-{
- return gd->mck_rate_hz;
-}
-
-unsigned long get_plla_clk_rate(void)
-{
- return gd->plla_rate_hz;
-}
-
-unsigned long get_pllb_clk_rate(void)
-{
- return gd->pllb_rate_hz;
-}
-
-u32 get_pllb_init(void)
-{
- return gd->at91_pllb_usb_init;
-}
-
static unsigned long at91_css_to_rate(unsigned long css)
{
switch (css) {
@@ -192,10 +162,7 @@ int at91_clock_init(unsigned long main_clock)
freq = gd->mck_rate_hz;
freq /= (1 << ((mckr & AT91_PMC_MCKR_PRES_MASK) >> 2)); /* prescale */
-#if defined(CONFIG_AT91RM9200)
- /* mdiv */
- gd->mck_rate_hz = freq / (1 + ((mckr & AT91_PMC_MCKR_MDIV_MASK) >> 8));
-#elif defined(CONFIG_AT91SAM9G20)
+#if defined(CONFIG_AT91SAM9G20)
/* mdiv ; (x >> 7) = ((x >> 8) * 2) */
gd->mck_rate_hz = (mckr & AT91_PMC_MCKR_MDIV_MASK) ?
freq / ((mckr & AT91_PMC_MCKR_MDIV_MASK) >> 7) : freq;
diff --git a/arch/arm/include/asm/arch-at91/clk.h b/arch/arm/include/asm/arch-at91/clk.h
index 457e6c9..f645327 100644
--- a/arch/arm/include/asm/arch-at91/clk.h
+++ b/arch/arm/include/asm/arch-at91/clk.h
@@ -26,13 +26,43 @@
#define __ASM_ARM_ARCH_CLK_H__
#include <asm/arch/hardware.h>
+#include <asm/global_data.h>
-unsigned long get_cpu_clk_rate(void);
-unsigned long get_main_clk_rate(void);
-unsigned long get_mck_clk_rate(void);
-unsigned long get_plla_clk_rate(void);
-unsigned long get_pllb_clk_rate(void);
-unsigned int get_pllb_init(void);
+static inline unsigned long get_cpu_clk_rate(void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ return gd->cpu_clk_rate_hz;
+}
+
+static inline unsigned long get_main_clk_rate(void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ return gd->main_clk_rate_hz;
+}
+
+static inline unsigned long get_mck_clk_rate(void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ return gd->mck_rate_hz;
+}
+
+static inline unsigned long get_plla_clk_rate(void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ return gd->plla_rate_hz;
+}
+
+static inline unsigned long get_pllb_clk_rate(void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ return gd->pllb_rate_hz;
+}
+
+static inline u32 get_pllb_init(void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ return gd->at91_pllb_usb_init;
+}
static inline unsigned long get_macb_pclk_rate(unsigned int dev_id)
{
--
1.7.5.4
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