dma: lpc32xx: add DMA driver

[u-boot] / drivers / dma / lpc32xx_dma.c

diff --git a/drivers/dma/lpc32xx_dma.c b/drivers/dma/lpc32xx_dma.c
new file mode 100644 (file)
index 0000000..955adfe
--- /dev/null
+++ b/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;
+}