Tegra2: Add more clock support
This adds functions to enable/disable clocks and reset to on-chip peripherals.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/cpu/armv7/tegra2/clock.c b/arch/arm/cpu/armv7/tegra2/clock.c
new file mode 100644
index 0000000..67eed14
--- /dev/null
+++ b/arch/arm/cpu/armv7/tegra2/clock.c
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/* Tegra2 Clock control functions */
+
+#include <asm/io.h>
+#include <asm/arch/clk_rst.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/timer.h>
+#include <asm/arch/tegra2.h>
+#include <common.h>
+
+#ifdef DEBUG
+#define assert(x) \
+ ({ if (!(x)) printf("Assertion failure '%s' %s line %d\n", \
+ #x, __FILE__, __LINE__); })
+#else
+#define assert(x)
+#endif
+
+/*
+ * Get the oscillator frequency, from the corresponding hardware configuration
+ * field.
+ */
+enum clock_osc_freq clock_get_osc_freq(void)
+{
+ struct clk_rst_ctlr *clkrst =
+ (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 reg;
+
+ reg = readl(&clkrst->crc_osc_ctrl);
+ return (reg & OSC_FREQ_MASK) >> OSC_FREQ_SHIFT;
+}
+
+unsigned long clock_start_pll(enum clock_pll_id clkid, u32 divm, u32 divn,
+ u32 divp, u32 cpcon, u32 lfcon)
+{
+ struct clk_rst_ctlr *clkrst =
+ (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 data;
+ struct clk_pll *pll;
+
+ assert(clock_pll_id_isvalid(clkid));
+ pll = &clkrst->crc_pll[clkid];
+
+ /*
+ * We cheat by treating all PLL (except PLLU) in the same fashion.
+ * This works only because:
+ * - same fields are always mapped at same offsets, except DCCON
+ * - DCCON is always 0, doesn't conflict
+ * - M,N, P of PLLP values are ignored for PLLP
+ */
+ data = (cpcon << PLL_CPCON_SHIFT) | (lfcon << PLL_LFCON_SHIFT);
+ writel(data, &pll->pll_misc);
+
+ data = (divm << PLL_DIVM_SHIFT) | (divn << PLL_DIVN_SHIFT) |
+ (0 << PLL_BYPASS_SHIFT) | (1 << PLL_ENABLE_SHIFT);
+
+ if (clkid == CLOCK_PLL_ID_USB)
+ data |= divp << PLLU_VCO_FREQ_SHIFT;
+ else
+ data |= divp << PLL_DIVP_SHIFT;
+ writel(data, &pll->pll_base);
+
+ /* calculate the stable time */
+ return timer_get_us() + CLOCK_PLL_STABLE_DELAY_US;
+}
+
+void clock_set_enable(enum periph_id periph_id, int enable)
+{
+ struct clk_rst_ctlr *clkrst =
+ (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 *clk = &clkrst->crc_clk_out_enb[PERIPH_REG(periph_id)];
+ u32 reg;
+
+ /* Enable/disable the clock to this peripheral */
+ assert(clock_periph_id_isvalid(periph_id));
+ reg = readl(clk);
+ if (enable)
+ reg |= PERIPH_MASK(periph_id);
+ else
+ reg &= ~PERIPH_MASK(periph_id);
+ writel(reg, clk);
+}
+
+void clock_enable(enum periph_id clkid)
+{
+ clock_set_enable(clkid, 1);
+}
+
+void clock_disable(enum periph_id clkid)
+{
+ clock_set_enable(clkid, 0);
+}
+
+void reset_set_enable(enum periph_id periph_id, int enable)
+{
+ struct clk_rst_ctlr *clkrst =
+ (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 *reset = &clkrst->crc_rst_dev[PERIPH_REG(periph_id)];
+ u32 reg;
+
+ /* Enable/disable reset to the peripheral */
+ assert(clock_periph_id_isvalid(periph_id));
+ reg = readl(reset);
+ if (enable)
+ reg |= PERIPH_MASK(periph_id);
+ else
+ reg &= ~PERIPH_MASK(periph_id);
+ writel(reg, reset);
+}
+
+void reset_periph(enum periph_id periph_id, int us_delay)
+{
+ /* Put peripheral into reset */
+ reset_set_enable(periph_id, 1);
+ udelay(us_delay);
+
+ /* Remove reset */
+ reset_set_enable(periph_id, 0);
+
+ udelay(us_delay);
+}
+
+void reset_cmplx_set_enable(int cpu, int which, int reset)
+{
+ struct clk_rst_ctlr *clkrst =
+ (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 mask;
+
+ /* Form the mask, which depends on the cpu chosen. Tegra2 has 2 */
+ assert(cpu >= 0 && cpu < 2);
+ mask = which << cpu;
+
+ /* either enable or disable those reset for that CPU */
+ if (reset)
+ writel(mask, &clkrst->crc_cpu_cmplx_set);
+ else
+ writel(mask, &clkrst->crc_cpu_cmplx_clr);
+}