dma: lpc32xx: add DMA driver

Incorporate DMA driver from legacy LPCLinux NXP BSP.
The files taken from the legacy patch are:
- lpc32xx DMA driver
- lpc3250 header file DMA registers definition.

The legacy driver was updated and clean-up as part of the integration with the latest u-boot.

Signed-off-by: Sylvain Lemieux <slemieux@tycoint.com>
Acked-by: Marek Vasut <marex@denx.de>
Tested-by: Vladimir Zapolskiy <vz@mleia.com>

arch/arm/cpu/arm926ejs/lpc32xx/devices.c

@@ -41,6 +41,13 @@ void lpc32xx_uart_init(unsigned int uart_id)
 	       &clk->u3clk + (uart_id - 3));
 }
 
+void lpc32xx_dma_init(void)
+{
+	/* Enable DMA interface */
+	writel(DMA_CLK_ENABLE, &clk->dmaclk_ctrl);
+
+}
+
 void lpc32xx_mac_init(void)
 {
 	/* Enable MAC interface */

arch/arm/include/asm/arch-lpc32xx/clk.h

@@ -158,6 +158,9 @@ struct clk_pm_regs {
 #define CLK_NAND_SLC_SELECT		(1 << 2)
 #define CLK_NAND_MLC_INT		(1 << 5)
 
+/* DMA Clock Control Register bits */
+#define DMA_CLK_ENABLE			(1 << 0)
+
 /* SSP Clock Control Register bits */
 #define CLK_SSP0_ENABLE_CLOCK		(1 << 0)
 

arch/arm/include/asm/arch-lpc32xx/dma.h

@@ -0,0 +1,67 @@
+/*
+ * LPC32xx DMA Controller Interface
+ *
+ * Copyright (C) 2008 by NXP Semiconductors
+ * @Author: Kevin Wells
+ * @Descr: Definitions for LPC3250 chip
+ * @References: NXP LPC3250 User's Guide
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _LPC32XX_DMA_H
+#define _LPC32XX_DMA_H
+
+#include <common.h>
+
+/*
+ * DMA linked list structure used with a channel's LLI register;
+ * refer to UM10326, "LPC32x0 and LPC32x0/01 User manual" - Rev. 3
+ * tables 84, 85, 86 & 87 for details.
+ */
+struct lpc32xx_dmac_ll {
+	u32 dma_src;
+	u32 dma_dest;
+	u32 next_lli;
+	u32 next_ctrl;
+};
+
+/* control register definitions */
+#define DMAC_CHAN_INT_TC_EN	(1 << 31) /* channel terminal count interrupt */
+#define DMAC_CHAN_DEST_AUTOINC	(1 << 27) /* automatic destination increment */
+#define DMAC_CHAN_SRC_AUTOINC	(1 << 26) /* automatic source increment */
+#define DMAC_CHAN_DEST_AHB1	(1 << 25) /* AHB1 master for dest. transfer */
+#define DMAC_CHAN_DEST_WIDTH_32	(1 << 22) /* Destination data width selection */
+#define DMAC_CHAN_SRC_WIDTH_32	(1 << 19) /* Source data width selection */
+#define DMAC_CHAN_DEST_BURST_1	0
+#define DMAC_CHAN_DEST_BURST_4	(1 << 15) /* Destination data burst size */
+#define DMAC_CHAN_SRC_BURST_1	0
+#define DMAC_CHAN_SRC_BURST_4	(1 << 12) /* Source data burst size */
+
+/*
+ * config_ch register definitions
+ * DMAC_CHAN_FLOW_D_xxx: flow control with DMA as the controller
+ * DMAC_DEST_PERIP: Macro for loading destination peripheral
+ * DMAC_SRC_PERIP: Macro for loading source peripheral
+ */
+#define DMAC_CHAN_FLOW_D_M2P	(0x1 << 11)
+#define DMAC_CHAN_FLOW_D_P2M	(0x2 << 11)
+#define DMAC_DEST_PERIP(n)	(((n) & 0x1F) << 6)
+#define DMAC_SRC_PERIP(n)	(((n) & 0x1F) << 1)
+
+/*
+ * config_ch register definitions
+ * (source and destination peripheral ID numbers).
+ * These can be used with the DMAC_DEST_PERIP and DMAC_SRC_PERIP macros.
+ */
+#define DMA_PERID_NAND1		1
+
+/* Channel enable bit */
+#define DMAC_CHAN_ENABLE	(1 << 0)
+
+int lpc32xx_dma_get_channel(void);
+int lpc32xx_dma_start_xfer(unsigned int channel,
+			   const struct lpc32xx_dmac_ll *desc, u32 config);
+int lpc32xx_dma_wait_status(unsigned int channel);
+
+#endif /* _LPC32XX_DMA_H */

arch/arm/include/asm/arch-lpc32xx/sys_proto.h

@@ -10,6 +10,7 @@
 #include <asm/arch/emc.h>
 
 void lpc32xx_uart_init(unsigned int uart_id);
+void lpc32xx_dma_init(void);
 void lpc32xx_mac_init(void);
 void lpc32xx_mlc_nand_init(void);
 void lpc32xx_slc_nand_init(void);

drivers/dma/Makefile

@@ -10,3 +10,4 @@ obj-$(CONFIG_APBH_DMA) += apbh_dma.o
 obj-$(CONFIG_FSL_DMA) += fsl_dma.o
 obj-$(CONFIG_TI_KSNAV) += keystone_nav.o keystone_nav_cfg.o
 obj-$(CONFIG_TI_EDMA3) += ti-edma3.o
+obj-$(CONFIG_DMA_LPC32XX) += lpc32xx_dma.o

drivers/dma/lpc32xx_dma.c

@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2008 by NXP Semiconductors
+ * @Author: Kevin Wells
+ * @Descr: LPC3250 DMA controller interface support functions
+ *
+ * Copyright (c) 2015 Tyco Fire Protection Products.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <asm/arch/dma.h>
+#include <asm/arch/cpu.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/io.h>
+
+/* DMA controller channel register structure */
+struct dmac_chan_reg {
+	u32 src_addr;
+	u32 dest_addr;
+	u32 lli;
+	u32 control;
+	u32 config_ch;
+	u32 reserved[3];
+};
+
+/* DMA controller register structures */
+struct dma_reg {
+	u32 int_stat;
+	u32 int_tc_stat;
+	u32 int_tc_clear;
+	u32 int_err_stat;
+	u32 int_err_clear;
+	u32 raw_tc_stat;
+	u32 raw_err_stat;
+	u32 chan_enable;
+	u32 sw_burst_req;
+	u32 sw_single_req;
+	u32 sw_last_burst_req;
+	u32 sw_last_single_req;
+	u32 config;
+	u32 sync;
+	u32 reserved[50];
+	struct dmac_chan_reg dma_chan[8];
+};
+
+#define DMA_NO_OF_CHANNELS	8
+
+/* config register definitions */
+#define DMAC_CTRL_ENABLE	(1 << 0) /* For enabling the DMA controller */
+
+static u32 alloc_ch;
+
+static struct dma_reg *dma = (struct dma_reg *)DMA_BASE;
+
+int lpc32xx_dma_get_channel(void)
+{
+	int i;
+
+	if (!alloc_ch) { /* First time caller */
+		/*
+		 * DMA clock are enable by "lpc32xx_dma_init()" and should
+		 * be call by board "board_early_init_f()" function.
+		 */
+
+		/*
+		 * Make sure DMA controller and all channels are disabled.
+		 * Controller is in little-endian mode. Disable sync signals.
+		 */
+		writel(0, &dma->config);
+		writel(0, &dma->sync);
+
+		/* Clear interrupt and error statuses */
+		writel(0xFF, &dma->int_tc_clear);
+		writel(0xFF, &dma->raw_tc_stat);
+		writel(0xFF, &dma->int_err_clear);
+		writel(0xFF, &dma->raw_err_stat);
+
+		/* Enable DMA controller */
+		writel(DMAC_CTRL_ENABLE, &dma->config);
+	}
+
+	i = ffz(alloc_ch);
+
+	/* Check if all the available channels are busy */
+	if (unlikely(i == DMA_NO_OF_CHANNELS))
+		return -1;
+	alloc_ch |= BIT_MASK(i);
+	return i;
+}
+
+int lpc32xx_dma_start_xfer(unsigned int channel,
+			   const struct lpc32xx_dmac_ll *desc, u32 config)
+{
+	if (unlikely(((BIT_MASK(channel) & alloc_ch) == 0) ||
+		     (channel >= DMA_NO_OF_CHANNELS))) {
+		error("Request for xfer on unallocated channel %d", channel);
+		return -1;
+	}
+	writel(BIT_MASK(channel), &dma->int_tc_clear);
+	writel(BIT_MASK(channel), &dma->int_err_clear);
+	writel(desc->dma_src, &dma->dma_chan[channel].src_addr);
+	writel(desc->dma_dest, &dma->dma_chan[channel].dest_addr);
+	writel(desc->next_lli, &dma->dma_chan[channel].lli);
+	writel(desc->next_ctrl, &dma->dma_chan[channel].control);
+	writel(config, &dma->dma_chan[channel].config_ch);
+
+	return 0;
+}
+
+int lpc32xx_dma_wait_status(unsigned int channel)
+{
+	unsigned long start;
+	u32 reg;
+
+	/* Check if given channel is valid */
+	if (unlikely(channel >= DMA_NO_OF_CHANNELS)) {
+		error("Request for status on unallocated channel %d", channel);
+		return -1;
+	}
+
+	start = get_timer(0);
+	while (1) {
+		reg = readl(&dma->raw_tc_stat);
+		reg |= readl(dma->raw_err_stat);
+		if (reg & BIT_MASK(channel))
+			break;
+
+		if (get_timer(start) > CONFIG_SYS_HZ) {
+			error("DMA status timeout channel %d\n", channel);
+			return -ETIMEDOUT;
+		}
+		udelay(1);
+	}
+
+	if (unlikely(readl(&dma->raw_err_stat) & BIT_MASK(channel))) {
+		setbits_le32(&dma->int_err_clear, BIT_MASK(channel));
+		setbits_le32(&dma->raw_err_stat, BIT_MASK(channel));
+		error("DMA error on channel %d\n", channel);
+		return -1;
+	}
+	setbits_le32(&dma->int_tc_clear, BIT_MASK(channel));
+	setbits_le32(&dma->raw_tc_stat, BIT_MASK(channel));
+	return 0;
+}