[U-Boot] [PATCH 3/6] tegra: Add a function mux feature

[Simon Glass]

funcmux permits selection of config options for particular peripherals,
such as the pins that are used for that peripheral, if there are several
options.

Add UART selection to start with.

Signed-off-by: Simon Glass <sjg at chromium.org>
---
 arch/arm/cpu/armv7/tegra2/Makefile         |    2 +-
 arch/arm/cpu/armv7/tegra2/funcmux.c        |   80 ++++++++++++++++++++++++++++
 arch/arm/include/asm/arch-tegra2/funcmux.h |   44 +++++++++++++++
 3 files changed, 125 insertions(+), 1 deletions(-)
 create mode 100644 arch/arm/cpu/armv7/tegra2/funcmux.c
 create mode 100644 arch/arm/include/asm/arch-tegra2/funcmux.h

diff --git a/arch/arm/cpu/armv7/tegra2/Makefile b/arch/arm/cpu/armv7/tegra2/Makefile
index 955c3b6..f668a81 100644
--- a/arch/arm/cpu/armv7/tegra2/Makefile
+++ b/arch/arm/cpu/armv7/tegra2/Makefile
@@ -33,7 +33,7 @@ include $(TOPDIR)/config.mk
 LIB	=  $(obj)lib$(SOC).o
 
 SOBJS	:= lowlevel_init.o
-COBJS	:= ap20.o board.o clock.o pinmux.o sys_info.o timer.o
+COBJS	:= ap20.o board.o clock.o funcmux.o pinmux.o sys_info.o timer.o
 
 SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
 OBJS	:= $(addprefix $(obj),$(COBJS) $(SOBJS))
diff --git a/arch/arm/cpu/armv7/tegra2/funcmux.c b/arch/arm/cpu/armv7/tegra2/funcmux.c
new file mode 100644
index 0000000..7651cb4
--- /dev/null
+++ b/arch/arm/cpu/armv7/tegra2/funcmux.c
@@ -0,0 +1,80 @@
+/*
+ * 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 high-level function multiplexing */
+#include <common.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/pinmux.h>
+
+static void enable_uart(enum periph_id pid)
+{
+	/* Assert UART reset and enable clock */
+	reset_set_enable(pid, 1);
+	clock_enable(pid);
+	clock_ll_set_source(pid, 0);	/* UARTx_CLK_SRC = 00, PLLP_OUT0 */
+
+	/* wait for 2us */
+	udelay(2);
+
+	/* De-assert reset to UART */
+	reset_set_enable(pid, 0);
+}
+
+void funcmux_select(enum periph_id id, int func)
+{
+	switch (id) {
+	case PERIPH_ID_UART1:
+		pinmux_set_func(PINGRP_IRRX, PMUX_FUNC_UARTA);
+		pinmux_set_func(PINGRP_IRTX, PMUX_FUNC_UARTA);
+		pinmux_tristate_disable(PINGRP_IRRX);
+		pinmux_tristate_disable(PINGRP_IRTX);
+		break;
+
+	case PERIPH_ID_UART2:
+		pinmux_set_func(PINGRP_UAD, PMUX_FUNC_IRDA);
+		pinmux_tristate_disable(PINGRP_UAD);
+		break;
+
+	case PERIPH_ID_UART4:
+		pinmux_set_func(PINGRP_GMC, PMUX_FUNC_UARTD);
+		pinmux_tristate_disable(PINGRP_GMC);
+		break;
+
+	default:
+		debug("%s: invalid periph_id %d", __func__, id);
+		break;
+	}
+}
+
+void funcmux_enable_f(enum periph_id id)
+{
+	switch (id) {
+	case PERIPH_ID_UART1:
+	case PERIPH_ID_UART2:
+	case PERIPH_ID_UART4:
+		enable_uart(id);
+		break;
+
+	default:
+		debug("%s: invalid periph_id %d", __func__, id);
+		break;
+	}
+}
diff --git a/arch/arm/include/asm/arch-tegra2/funcmux.h b/arch/arm/include/asm/arch-tegra2/funcmux.h
new file mode 100644
index 0000000..f357ab4
--- /dev/null
+++ b/arch/arm/include/asm/arch-tegra2/funcmux.h
@@ -0,0 +1,44 @@
+/*
+ * 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 high-level function multiplexing */
+
+/**
+ * Select a config for a particular peripheral.
+ *
+ * Each peripheral can operate through a number of configurations,
+ * which are sets of pins that it uses to bring out its signals.
+ * The basic config is 0, and higher numbers indicate different
+ * pinmux settings to bring the peripheral out on other pins,
+ *
+ * @param id		Peripheral id
+ * @param config	Configuration to use (generally 0)
+ */
+void funcmux_select(enum periph_id id, int config);
+
+/**
+ * Enable a particular peripheral prior to relocation, when the full clock
+ * features are not available. After relocation you should call
+ * clock_start_periph_pll() for this.
+ *
+ * This function currently only supports enabling the UARTs.
+ */
+void funcmux_enable_f(enum periph_id id);
-- 
1.7.3.1