gpio: Add Multi-Function-Pin configuration driver for Marvell SoCs

Most of the Marvell SoCs has Multi Function Pin (MFP) configuration registers
For ex. ARMADA100.

These registers are programmed to expose the specific functionality
associated with respective SoC Pins

This driver provides configuration APIs,
using them, configuration need to be done in board specific code

for ex- following code configures MFPs 107 and 108 for UART_TX/RX functionality

int board_early_init_f(void)
{
        u32 mfp_cfg[] = {
                /* Console on UART1 */
                MFP107_UART1_RXD,
                MFP108_UART1_TXD,
                MFP_EOC         /*End of configureation*/
        };
        /* configure MFP's */
        mfp_config(mfp_cfg);
        return 0;
}

Signed-off-by: Prafulla Wadaskar <prafulla@marvell.com>

3 files changed, 188 insertions, 0 deletions

diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 398024c..a5fa2b5 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -27,6 +27,7 @@ LIB 	:= $(obj)libgpio.o
 
 COBJS-$(CONFIG_AT91_GPIO)	+= at91_gpio.o
 COBJS-$(CONFIG_KIRKWOOD_GPIO)	+= kw_gpio.o
+COBJS-$(CONFIG_MARVELL_MFP)	+= mvmfp.o
 COBJS-$(CONFIG_MXC_GPIO)	+= mxc_gpio.o
 COBJS-$(CONFIG_PCA953X)		+= pca953x.o
 COBJS-$(CONFIG_S5P)		+= s5p_gpio.o
diff --git a/drivers/gpio/mvmfp.c b/drivers/gpio/mvmfp.c
new file mode 100644
index 0000000..5646ed4
--- /dev/null
+++ b/drivers/gpio/mvmfp.c
@@ -0,0 +1,87 @@
+/*
+ * (C) Copyright 2010
+ * Marvell Semiconductor <www.marvell.com>
+ * Written-by: Prafulla Wadaskar <prafulla@marvell.com>,
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <mvmfp.h>
+#include <asm/arch/mfp.h>
+#ifdef CONFIG_ARMADA100
+#include <asm/arch/armada100.h>
+#else
+#error Unsupported SoC...
+#endif
+
+/*
+ * mfp_config
+ *
+ * On most of Marvell SoCs (ex. ARMADA100) there is Multi-Funtion-Pin
+ * configuration registers to configure each GPIO/Function pin on the
+ * SoC.
+ *
+ * This function reads the array of values for
+ * MFPR_X registers and programms them into respective
+ * Multi-Function Pin registers.
+ * It supports - Alternate Function Selection programming.
+ *
+ * Whereas,
+ * The Configureation value is constructed using MFP()
+ * array consists of 32bit values as defined in MFP(xx,xx..) macro
+ */
+void mfp_config(u32 *mfp_cfgs)
+{
+	u32 *p_mfpr = NULL;
+	u32 cfg_val, val;
+
+	do {
+		cfg_val = *mfp_cfgs++;
+		/* exit if End of configuration table detected */
+		if (cfg_val == MFP_EOC)
+			break;
+
+		p_mfpr = (u32 *)(MV_MFPR_BASE
+				+ MFP_REG_GET_OFFSET(cfg_val));
+
+		/* Write a mfg register as per configuration */
+		val = 0;
+		if (cfg_val & MFP_AF_FLAG)
+			/* Abstract and program Afternate-Func Selection */
+			val |= cfg_val & MFP_AF_MASK;
+		if (cfg_val & MFP_EDGE_FLAG)
+			/* Abstract and program Edge configuration */
+			val |= cfg_val & MFP_LPM_EDGE_MASK;
+		if (cfg_val & MFP_DRIVE_FLAG)
+			/* Abstract and program Drive configuration */
+			val |= cfg_val & MFP_DRIVE_MASK;
+		if (cfg_val & MFP_PULL_FLAG)
+			/* Abstract and program Pullup/down configuration */
+			val |= cfg_val & MFP_PULL_MASK;
+
+		writel(val, p_mfpr);
+	} while (1);
+	/*
+	 * perform a read-back of any MFPR register to make sure the
+	 * previous writings are finished
+	 */
+	readl(p_mfpr);
+}
diff --git a/include/mvmfp.h b/include/mvmfp.h
new file mode 100644
index 0000000..0b36393
--- /dev/null
+++ b/include/mvmfp.h
@@ -0,0 +1,100 @@
+/*
+ * (C) Copyright 2010
+ * Marvell Semiconductor <www.marvell.com>
+ * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#ifndef __MVMFP_H
+#define __MVMFP_H
+
+/*
+ * Header file for MultiFunctionPin (MFP) Configururation framework
+ *
+ * Processors Supported:
+ * 1. Marvell ARMADA100 Processors
+ *
+ * processor to be supported should be added here
+ */
+
+/*
+ * MFP configuration is represented by a 32-bit unsigned integer
+ */
+#define MFP(_off, _pull, _pF, _drv, _dF, _edge, _eF, _afn, _aF) ( \
+	/* bits 31..16 - MFP Register Offset */	(((_off) & 0xffff) << 16) | \
+	/* bits 15..13 - Run Mode Pull State */	(((_pull) & 0x7) << 13) | \
+	/* bit  12     - Unused */ \
+	/* bits 11..10 - Driver Strength */	(((_drv) & 0x3) << 10) | \
+	/* bit  09     - Pull State flag */	(((_pF) & 0x1) << 9) | \
+	/* bit  08     - Drv-strength flag */	(((_dF) & 0x1) << 8) | \
+	/* bit  07     - Edge-det flag */	(((_eF) & 0x1) << 7) | \
+	/* bits 06..04 - Edge Detection */	(((_edge) & 0x7) << 4) | \
+	/* bits 03..00 - Alt-fun flag */	(((_aF) & 0x1) << 3) | \
+	/* bits Alternate-fun select */		((_afn) & 0x7))
+
+/*
+ * to facilitate the definition, the following macros are provided
+ *
+ * 				    offset, pull,pF, drv,dF, edge,eF ,afn,aF
+ */
+#define MFP_OFFSET_MASK		MFP(0xffff,    0,0,    0,0,     0,0,   0,0)
+#define MFP_REG(x)		MFP(x,         0,0,    0,0,     0,0,   0,0)
+#define MFP_REG_GET_OFFSET(x)	((x & MFP_OFFSET_MASK) >> 16)
+
+#define MFP_AF_FLAG		MFP(0x0000,    0,0,    0,0,     0,0,   0,1)
+#define MFP_DRIVE_FLAG		MFP(0x0000,    0,0,    0,1,     0,0,   0,0)
+#define MFP_EDGE_FLAG		MFP(0x0000,    0,0,    0,0,     0,1,   0,0)
+#define MFP_PULL_FLAG		MFP(0x0000,    0,1,    0,0,     0,0,   0,0)
+
+#define MFP_AF0			MFP(0x0000,    0,0,    0,0,     0,0,   0,1)
+#define MFP_AF1			MFP(0x0000,    0,0,    0,0,     0,0,   1,1)
+#define MFP_AF2			MFP(0x0000,    0,0,    0,0,     0,0,   2,1)
+#define MFP_AF3			MFP(0x0000,    0,0,    0,0,     0,0,   3,1)
+#define MFP_AF4			MFP(0x0000,    0,0,    0,0,     0,0,   4,1)
+#define MFP_AF5			MFP(0x0000,    0,0,    0,0,     0,0,   5,1)
+#define MFP_AF6			MFP(0x0000,    0,0,    0,0,     0,0,   6,1)
+#define MFP_AF7			MFP(0x0000,    0,0,    0,0,     0,0,   7,1)
+#define MFP_AF_MASK		MFP(0x0000,    0,0,    0,0,     0,0,   7,0)
+
+#define MFP_LPM_EDGE_NONE	MFP(0x0000,    0,0,    0,0,     0,1,   0,0)
+#define MFP_LPM_EDGE_RISE	MFP(0x0000,    0,0,    0,0,     1,1,   0,0)
+#define MFP_LPM_EDGE_FALL	MFP(0x0000,    0,0,    0,0,     2,1,   0,0)
+#define MFP_LPM_EDGE_BOTH	MFP(0x0000,    0,0,    0,0,     3,1,   0,0)
+#define MFP_LPM_EDGE_MASK	MFP(0x0000,    0,0,    0,0,     3,0,   0,0)
+
+#define MFP_DRIVE_VERY_SLOW	MFP(0x0000,    0,0,    0,1,     0,0,   0,0)
+#define MFP_DRIVE_SLOW		MFP(0x0000,    0,0,    1,1,     0,0,   0,0)
+#define MFP_DRIVE_MEDIUM	MFP(0x0000,    0,0,    2,1,     0,0,   0,0)
+#define MFP_DRIVE_FAST		MFP(0x0000,    0,0,    3,1,     0,0,   0,0)
+#define MFP_DRIVE_MASK		MFP(0x0000,    0,0,    3,0,     0,0,   0,0)
+
+#define MFP_PULL_NONE		MFP(0x0000,    0,1,    0,0,     0,0,   0,0)
+#define MFP_PULL_LOW		MFP(0x0000,    1,1,    0,0,     0,0,   0,0)
+#define MFP_PULL_HIGH		MFP(0x0000,    2,1,    0,0,     0,0,   0,0)
+#define MFP_PULL_BOTH		MFP(0x0000,    3,1,    0,0,     0,0,   0,0)
+#define MFP_PULL_FLOAT		MFP(0x0000,    4,1,    0,0,     0,0,   0,0)
+#define MFP_PULL_MASK		MFP(0x0000,    7,0,    0,0,     0,0,   0,0)
+
+#define MFP_EOC			0xffffffff	/* indicates end-of-conf */
+
+/* Functions */
+void mfp_config(u32 *mfp_cfgs);
+
+#endif /* __MVMFP_H */