LIB = $(obj)lib$(SOC).o
COBJS-$(CONFIG_USB_EHCI_TEGRA) += usb.o
+COBJS-$(CONFIG_PWM_TEGRA) += pwm.o
COBJS := $(COBJS-y)
SRCS := $(COBJS:.o=.c)
--- /dev/null
+/*
+ * Tegra2 pulse width frequency modulator definitions
+ *
+ * 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
+ */
+
+#include <common.h>
+#include <fdtdec.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/pwm.h>
+
+struct pwm_info {
+ struct pwm_ctlr *pwm; /* Registers for our pwm controller */
+ int pwm_node; /* PWM device tree node */
+} local;
+
+void pwm_enable(unsigned channel, int rate, int pulse_width, int freq_divider)
+{
+ u32 reg;
+
+ assert(channel < PWM_NUM_CHANNELS);
+
+ /* TODO: Can we use clock_adjust_periph_pll_div() here? */
+ clock_start_periph_pll(PERIPH_ID_PWM, CLOCK_ID_SFROM32KHZ, rate);
+
+ reg = PWM_ENABLE_MASK;
+ reg |= pulse_width << PWM_WIDTH_SHIFT;
+ reg |= freq_divider << PWM_DIVIDER_SHIFT;
+ writel(reg, &local.pwm[channel].control);
+ debug("%s: channel=%d, rate=%d\n", __func__, channel, rate);
+}
+
+int pwm_request(const void *blob, int node, const char *prop_name)
+{
+ int pwm_node;
+ u32 data[3];
+
+ if (fdtdec_get_int_array(blob, node, prop_name, data,
+ ARRAY_SIZE(data))) {
+ debug("%s: Cannot decode PWM property '%s'\n", __func__,
+ prop_name);
+ return -1;
+ }
+
+ pwm_node = fdt_node_offset_by_phandle(blob, data[0]);
+ if (pwm_node != local.pwm_node) {
+ debug("%s: PWM property '%s' phandle %d not recognised"
+ "- expecting %d\n", __func__, prop_name, data[0],
+ local.pwm_node);
+ return -1;
+ }
+ if (data[1] >= PWM_NUM_CHANNELS) {
+ debug("%s: PWM property '%s': invalid channel %u\n", __func__,
+ prop_name, data[1]);
+ return -1;
+ }
+
+ /*
+ * TODO: We could maintain a list of requests, but it might not be
+ * worth it for U-Boot.
+ */
+ return data[1];
+}
+
+int pwm_init(const void *blob)
+{
+ local.pwm_node = fdtdec_next_compatible(blob, 0,
+ COMPAT_NVIDIA_TEGRA20_PWM);
+ if (local.pwm_node < 0) {
+ debug("%s: Cannot find device tree node\n", __func__);
+ return -1;
+ }
+
+ local.pwm = (struct pwm_ctlr *)fdtdec_get_addr(blob, local.pwm_node,
+ "reg");
+ if (local.pwm == (struct pwm_ctlr *)FDT_ADDR_T_NONE) {
+ debug("%s: Cannot find pwm reg address\n", __func__);
+ return -1;
+ }
+ debug("Tegra PWM at %p, node %d\n", local.pwm, local.pwm_node);
+
+ return 0;
+}
--- /dev/null
+/*
+ * Tegra pulse width frequency modulator definitions
+ *
+ * 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
+ */
+
+#ifndef __ASM_ARCH_TEGRA_PWM_H
+#define __ASM_ARCH_TEGRA_PWM_H
+
+/* This is a single PWM channel */
+struct pwm_ctlr {
+ uint control; /* Control register */
+ uint reserved[3]; /* Space space */
+};
+
+#define PWM_NUM_CHANNELS 4
+
+/* PWM_CONTROLLER_PWM_CSR_0/1/2/3_0 */
+#define PWM_ENABLE_SHIFT 31
+#define PWM_ENABLE_MASK (0x1 << PWM_ENABLE_SHIFT)
+
+#define PWM_WIDTH_SHIFT 16
+#define PWM_WIDTH_MASK (0x7FFF << PWM_WIDTH_SHIFT)
+
+#define PWM_DIVIDER_SHIFT 0
+#define PWM_DIVIDER_MASK (0x1FFF << PWM_DIVIDER_SHIFT)
+
+/**
+ * Program the PWM with the given parameters.
+ *
+ * @param channel PWM channel to update
+ * @param rate Clock rate to use for PWM
+ * @param pulse_width high pulse width: 0=always low, 1=1/256 pulse high,
+ * n = n/256 pulse high
+ * @param freq_divider frequency divider value (1 to use rate as is)
+ */
+void pwm_enable(unsigned channel, int rate, int pulse_width, int freq_divider);
+
+/**
+ * Request a pwm channel as referenced by a device tree node.
+ *
+ * This channel can then be passed to pwm_enable().
+ *
+ * @param blob Device tree blob
+ * @param node Node containing reference to pwm
+ * @param prop_name Property name of pwm reference
+ * @return channel number, if ok, else -1
+ */
+int pwm_request(const void *blob, int node, const char *prop_name);
+
+/**
+ * Set up the pwm controller, by looking it up in the fdt.
+ *
+ * @return 0 if ok, -1 if the device tree node was not found or invalid.
+ */
+int pwm_init(const void *blob);
+
+#endif /* __ASM_ARCH_TEGRA_PWM_H */
#include <asm/arch/funcmux.h>
#include <asm/arch/pinmux.h>
#include <asm/arch/pmu.h>
+#include <asm/arch/pwm.h>
#include <asm/arch/tegra.h>
#include <asm/arch/usb.h>
#include <asm/arch-tegra/board.h>
#ifdef CONFIG_TEGRA_SPI
pin_mux_spi();
spi_init();
+#endif
+#ifdef CONFIG_PWM_TEGRA
+ if (pwm_init(gd->fdt_blob))
+ debug("%s: Failed to init pwm\n", __func__);
#endif
/* boot param addr */
gd->bd->bi_boot_params = (NV_PA_SDRAM_BASE + 0x100);
COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */
COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
+ COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */
COMPAT_COUNT,
};
COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
+ COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
};
const char *fdtdec_get_compatible(enum fdt_compat_id id)
projects / u-boot.git / commitdiff
