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-rw-r--r--arch/arm/mach-at91/armv7/clock.c175
1 files changed, 175 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/armv7/clock.c b/arch/arm/mach-at91/armv7/clock.c
new file mode 100644
index 0000000000..0bf453eff5
--- /dev/null
+++ b/arch/arm/mach-at91/armv7/clock.c
@@ -0,0 +1,175 @@
+/*
+ * [origin: Linux kernel linux/arch/arm/mach-at91/clock.c]
+ *
+ * Copyright (C) 2005 David Brownell
+ * Copyright (C) 2005 Ivan Kokshaysky
+ * Copyright (C) 2009 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ * Copyright (C) 2013 Bo Shen <voice.shen@atmel.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#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->arch.main_clk_rate_hz;
+ case AT91_PMC_MCKR_CSS_PLLA:
+ return gd->arch.plla_rate_hz;
+ }
+
+ return 0;
+}
+
+static u32 at91_pll_rate(u32 freq, u32 reg)
+{
+ unsigned mul, div;
+
+ div = reg & 0xff;
+ mul = (reg >> 18) & 0x7f;
+ if (div && mul) {
+ freq /= div;
+ freq *= mul + 1;
+ } else {
+ freq = 0;
+ }
+
+ return freq;
+}
+
+int at91_clock_init(unsigned long main_clock)
+{
+ unsigned freq, mckr;
+ struct at91_pmc *pmc = (struct at91_pmc *)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->arch.main_clk_rate_hz = main_clock;
+
+ /* report if PLLA is more than mildly overclocked */
+ gd->arch.plla_rate_hz = at91_pll_rate(main_clock, readl(&pmc->pllar));
+
+ /*
+ * MCK and CPU derive from one of those primary clocks.
+ * For now, assume this parentage won't change.
+ */
+ mckr = readl(&pmc->mckr);
+
+ /* plla divisor by 2 */
+ if (mckr & (1 << 12))
+ gd->arch.plla_rate_hz >>= 1;
+
+ gd->arch.mck_rate_hz = at91_css_to_rate(mckr & AT91_PMC_MCKR_CSS_MASK);
+ freq = gd->arch.mck_rate_hz;
+
+ /* prescale */
+ freq >>= mckr & AT91_PMC_MCKR_PRES_MASK;
+
+ switch (mckr & AT91_PMC_MCKR_MDIV_MASK) {
+ case AT91_PMC_MCKR_MDIV_2:
+ gd->arch.mck_rate_hz = freq / 2;
+ break;
+ case AT91_PMC_MCKR_MDIV_3:
+ gd->arch.mck_rate_hz = freq / 3;
+ break;
+ case AT91_PMC_MCKR_MDIV_4:
+ gd->arch.mck_rate_hz = freq / 4;
+ break;
+ default:
+ break;
+ }
+
+ gd->arch.cpu_clk_rate_hz = freq;
+
+ return 0;
+}
+
+void at91_plla_init(u32 pllar)
+{
+ struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
+
+ writel(pllar, &pmc->pllar);
+ while (!(readl(&pmc->sr) & (AT91_PMC_LOCKA | AT91_PMC_MCKRDY)))
+ ;
+}
+
+void at91_mck_init(u32 mckr)
+{
+ struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
+ u32 tmp;
+
+ tmp = readl(&pmc->mckr);
+ tmp &= ~(AT91_PMC_MCKR_CSS_MASK |
+ AT91_PMC_MCKR_PRES_MASK |
+ AT91_PMC_MCKR_MDIV_MASK |
+ AT91_PMC_MCKR_PLLADIV_2);
+#ifdef CPU_HAS_H32MXDIV
+ tmp &= ~AT91_PMC_MCKR_H32MXDIV;
+#endif
+
+ tmp |= mckr & (AT91_PMC_MCKR_CSS_MASK |
+ AT91_PMC_MCKR_PRES_MASK |
+ AT91_PMC_MCKR_MDIV_MASK |
+ AT91_PMC_MCKR_PLLADIV_2);
+#ifdef CPU_HAS_H32MXDIV
+ tmp |= mckr & AT91_PMC_MCKR_H32MXDIV;
+#endif
+
+ writel(tmp, &pmc->mckr);
+
+ while (!(readl(&pmc->sr) & AT91_PMC_MCKRDY))
+ ;
+}
+
+void at91_periph_clk_enable(int id)
+{
+ struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
+ u32 regval;
+
+ if (id > AT91_PMC_PCR_PID_MASK)
+ return;
+
+ regval = AT91_PMC_PCR_EN | AT91_PMC_PCR_CMD_WRITE | id;
+
+ writel(regval, &pmc->pcr);
+}
+
+void at91_periph_clk_disable(int id)
+{
+ struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
+ u32 regval;
+
+ if (id > AT91_PMC_PCR_PID_MASK)
+ return;
+
+ regval = AT91_PMC_PCR_CMD_WRITE | id;
+
+ writel(regval, &pmc->pcr);
+}