1 files changed, 362 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/spi/mxs_spi.c b/roms/u-boot/drivers/spi/mxs_spi.c
new file mode 100644
index 00000000..2b9f395a
--- /dev/null
+++ b/roms/u-boot/drivers/spi/mxs_spi.c
@@ -0,0 +1,362 @@
+/*
+ * Freescale i.MX28 SPI driver
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * NOTE: This driver only supports the SPI-controller chipselects,
+ *       GPIO driven chipselects are not supported.
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <spi.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/imx-common/dma.h>
+
+#define	MXS_SPI_MAX_TIMEOUT	1000000
+#define	MXS_SPI_PORT_OFFSET	0x2000
+#define MXS_SSP_CHIPSELECT_MASK		0x00300000
+#define MXS_SSP_CHIPSELECT_SHIFT	20
+
+#define MXSSSP_SMALL_TRANSFER	512
+
+struct mxs_spi_slave {
+	struct spi_slave	slave;
+	uint32_t		max_khz;
+	uint32_t		mode;
+	struct mxs_ssp_regs	*regs;
+};
+
+static inline struct mxs_spi_slave *to_mxs_slave(struct spi_slave *slave)
+{
+	return container_of(slave, struct mxs_spi_slave, slave);
+}
+
+void spi_init(void)
+{
+}
+
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+	/* MXS SPI: 4 ports and 3 chip selects maximum */
+	if (!mxs_ssp_bus_id_valid(bus) || cs > 2)
+		return 0;
+	else
+		return 1;
+}
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+				  unsigned int max_hz, unsigned int mode)
+{
+	struct mxs_spi_slave *mxs_slave;
+
+	if (!spi_cs_is_valid(bus, cs)) {
+		printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs);
+		return NULL;
+	}
+
+	mxs_slave = spi_alloc_slave(struct mxs_spi_slave, bus, cs);
+	if (!mxs_slave)
+		return NULL;
+
+	if (mxs_dma_init_channel(MXS_DMA_CHANNEL_AHB_APBH_SSP0 + bus))
+		goto err_init;
+
+	mxs_slave->max_khz = max_hz / 1000;
+	mxs_slave->mode = mode;
+	mxs_slave->regs = mxs_ssp_regs_by_bus(bus);
+
+	return &mxs_slave->slave;
+
+err_init:
+	free(mxs_slave);
+	return NULL;
+}
+
+void spi_free_slave(struct spi_slave *slave)
+{
+	struct mxs_spi_slave *mxs_slave = to_mxs_slave(slave);
+	free(mxs_slave);
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+	struct mxs_spi_slave *mxs_slave = to_mxs_slave(slave);
+	struct mxs_ssp_regs *ssp_regs = mxs_slave->regs;
+	uint32_t reg = 0;
+
+	mxs_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);
+
+	writel((slave->cs << MXS_SSP_CHIPSELECT_SHIFT) |
+	       SSP_CTRL0_BUS_WIDTH_ONE_BIT,
+	       &ssp_regs->hw_ssp_ctrl0);
+
+	reg = SSP_CTRL1_SSP_MODE_SPI | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS;
+	reg |= (mxs_slave->mode & SPI_CPOL) ? SSP_CTRL1_POLARITY : 0;
+	reg |= (mxs_slave->mode & SPI_CPHA) ? SSP_CTRL1_PHASE : 0;
+	writel(reg, &ssp_regs->hw_ssp_ctrl1);
+
+	writel(0, &ssp_regs->hw_ssp_cmd0);
+
+	mxs_set_ssp_busclock(slave->bus, mxs_slave->max_khz);
+
+	return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+}
+
+static void mxs_spi_start_xfer(struct mxs_ssp_regs *ssp_regs)
+{
+	writel(SSP_CTRL0_LOCK_CS, &ssp_regs->hw_ssp_ctrl0_set);
+	writel(SSP_CTRL0_IGNORE_CRC, &ssp_regs->hw_ssp_ctrl0_clr);
+}
+
+static void mxs_spi_end_xfer(struct mxs_ssp_regs *ssp_regs)
+{
+	writel(SSP_CTRL0_LOCK_CS, &ssp_regs->hw_ssp_ctrl0_clr);
+	writel(SSP_CTRL0_IGNORE_CRC, &ssp_regs->hw_ssp_ctrl0_set);
+}
+
+static int mxs_spi_xfer_pio(struct mxs_spi_slave *slave,
+			char *data, int length, int write, unsigned long flags)
+{
+	struct mxs_ssp_regs *ssp_regs = slave->regs;
+
+	if (flags & SPI_XFER_BEGIN)
+		mxs_spi_start_xfer(ssp_regs);
+
+	while (length--) {
+		/* We transfer 1 byte */
+#if defined(CONFIG_MX23)
+		writel(SSP_CTRL0_XFER_COUNT_MASK, &ssp_regs->hw_ssp_ctrl0_clr);
+		writel(1, &ssp_regs->hw_ssp_ctrl0_set);
+#elif defined(CONFIG_MX28)
+		writel(1, &ssp_regs->hw_ssp_xfer_size);
+#endif
+
+		if ((flags & SPI_XFER_END) && !length)
+			mxs_spi_end_xfer(ssp_regs);
+
+		if (write)
+			writel(SSP_CTRL0_READ, &ssp_regs->hw_ssp_ctrl0_clr);
+		else
+			writel(SSP_CTRL0_READ, &ssp_regs->hw_ssp_ctrl0_set);
+
+		writel(SSP_CTRL0_RUN, &ssp_regs->hw_ssp_ctrl0_set);
+
+		if (mxs_wait_mask_set(&ssp_regs->hw_ssp_ctrl0_reg,
+			SSP_CTRL0_RUN, MXS_SPI_MAX_TIMEOUT)) {
+			printf("MXS SPI: Timeout waiting for start\n");
+			return -ETIMEDOUT;
+		}
+
+		if (write)
+			writel(*data++, &ssp_regs->hw_ssp_data);
+
+		writel(SSP_CTRL0_DATA_XFER, &ssp_regs->hw_ssp_ctrl0_set);
+
+		if (!write) {
+			if (mxs_wait_mask_clr(&ssp_regs->hw_ssp_status_reg,
+				SSP_STATUS_FIFO_EMPTY, MXS_SPI_MAX_TIMEOUT)) {
+				printf("MXS SPI: Timeout waiting for data\n");
+				return -ETIMEDOUT;
+			}
+
+			*data = readl(&ssp_regs->hw_ssp_data);
+			data++;
+		}
+
+		if (mxs_wait_mask_clr(&ssp_regs->hw_ssp_ctrl0_reg,
+			SSP_CTRL0_RUN, MXS_SPI_MAX_TIMEOUT)) {
+			printf("MXS SPI: Timeout waiting for finish\n");
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
+static int mxs_spi_xfer_dma(struct mxs_spi_slave *slave,
+			char *data, int length, int write, unsigned long flags)
+{
+	const int xfer_max_sz = 0xff00;
+	const int desc_count = DIV_ROUND_UP(length, xfer_max_sz) + 1;
+	struct mxs_ssp_regs *ssp_regs = slave->regs;
+	struct mxs_dma_desc *dp;
+	uint32_t ctrl0;
+	uint32_t cache_data_count;
+	const uint32_t dstart = (uint32_t)data;
+	int dmach;
+	int tl;
+	int ret = 0;
+
+#if defined(CONFIG_MX23)
+	const int mxs_spi_pio_words = 1;
+#elif defined(CONFIG_MX28)
+	const int mxs_spi_pio_words = 4;
+#endif
+
+	ALLOC_CACHE_ALIGN_BUFFER(struct mxs_dma_desc, desc, desc_count);
+
+	memset(desc, 0, sizeof(struct mxs_dma_desc) * desc_count);
+
+	ctrl0 = readl(&ssp_regs->hw_ssp_ctrl0);
+	ctrl0 |= SSP_CTRL0_DATA_XFER;
+
+	if (flags & SPI_XFER_BEGIN)
+		ctrl0 |= SSP_CTRL0_LOCK_CS;
+	if (!write)
+		ctrl0 |= SSP_CTRL0_READ;
+
+	if (length % ARCH_DMA_MINALIGN)
+		cache_data_count = roundup(length, ARCH_DMA_MINALIGN);
+	else
+		cache_data_count = length;
+
+	/* Flush data to DRAM so DMA can pick them up */
+	if (write)
+		flush_dcache_range(dstart, dstart + cache_data_count);
+
+	/* Invalidate the area, so no writeback into the RAM races with DMA */
+	invalidate_dcache_range(dstart, dstart + cache_data_count);
+
+	dmach = MXS_DMA_CHANNEL_AHB_APBH_SSP0 + slave->slave.bus;
+
+	dp = desc;
+	while (length) {
+		dp->address = (dma_addr_t)dp;
+		dp->cmd.address = (dma_addr_t)data;
+
+		/*
+		 * This is correct, even though it does indeed look insane.
+		 * I hereby have to, wholeheartedly, thank Freescale Inc.,
+		 * for always inventing insane hardware and keeping me busy
+		 * and employed ;-)
+		 */
+		if (write)
+			dp->cmd.data = MXS_DMA_DESC_COMMAND_DMA_READ;
+		else
+			dp->cmd.data = MXS_DMA_DESC_COMMAND_DMA_WRITE;
+
+		/*
+		 * The DMA controller can transfer large chunks (64kB) at
+		 * time by setting the transfer length to 0. Setting tl to
+		 * 0x10000 will overflow below and make .data contain 0.
+		 * Otherwise, 0xff00 is the transfer maximum.
+		 */
+		if (length >= 0x10000)
+			tl = 0x10000;
+		else
+			tl = min(length, xfer_max_sz);
+
+		dp->cmd.data |=
+			((tl & 0xffff) << MXS_DMA_DESC_BYTES_OFFSET) |
+			(mxs_spi_pio_words << MXS_DMA_DESC_PIO_WORDS_OFFSET) |
+			MXS_DMA_DESC_HALT_ON_TERMINATE |
+			MXS_DMA_DESC_TERMINATE_FLUSH;
+
+		data += tl;
+		length -= tl;
+
+		if (!length) {
+			dp->cmd.data |= MXS_DMA_DESC_IRQ | MXS_DMA_DESC_DEC_SEM;
+
+			if (flags & SPI_XFER_END) {
+				ctrl0 &= ~SSP_CTRL0_LOCK_CS;
+				ctrl0 |= SSP_CTRL0_IGNORE_CRC;
+			}
+		}
+
+		/*
+		 * Write CTRL0, CMD0, CMD1 and XFER_SIZE registers in
+		 * case of MX28, write only CTRL0 in case of MX23 due
+		 * to the difference in register layout. It is utterly
+		 * essential that the XFER_SIZE register is written on
+		 * a per-descriptor basis with the same size as is the
+		 * descriptor!
+		 */
+		dp->cmd.pio_words[0] = ctrl0;
+#ifdef CONFIG_MX28
+		dp->cmd.pio_words[1] = 0;
+		dp->cmd.pio_words[2] = 0;
+		dp->cmd.pio_words[3] = tl;
+#endif
+
+		mxs_dma_desc_append(dmach, dp);
+
+		dp++;
+	}
+
+	if (mxs_dma_go(dmach))
+		ret = -EINVAL;
+
+	/* The data arrived into DRAM, invalidate cache over them */
+	if (!write)
+		invalidate_dcache_range(dstart, dstart + cache_data_count);
+
+	return ret;
+}
+
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
+		const void *dout, void *din, unsigned long flags)
+{
+	struct mxs_spi_slave *mxs_slave = to_mxs_slave(slave);
+	struct mxs_ssp_regs *ssp_regs = mxs_slave->regs;
+	int len = bitlen / 8;
+	char dummy;
+	int write = 0;
+	char *data = NULL;
+	int dma = 1;
+
+	if (bitlen == 0) {
+		if (flags & SPI_XFER_END) {
+			din = (void *)&dummy;
+			len = 1;
+		} else
+			return 0;
+	}
+
+	/* Half-duplex only */
+	if (din && dout)
+		return -EINVAL;
+	/* No data */
+	if (!din && !dout)
+		return 0;
+
+	if (dout) {
+		data = (char *)dout;
+		write = 1;
+	} else if (din) {
+		data = (char *)din;
+		write = 0;
+	}
+
+	/*
+	 * Check for alignment, if the buffer is aligned, do DMA transfer,
+	 * PIO otherwise. This is a temporary workaround until proper bounce
+	 * buffer is in place.
+	 */
+	if (dma) {
+		if (((uint32_t)data) & (ARCH_DMA_MINALIGN - 1))
+			dma = 0;
+		if (((uint32_t)len) & (ARCH_DMA_MINALIGN - 1))
+			dma = 0;
+	}
+
+	if (!dma || (len < MXSSSP_SMALL_TRANSFER)) {
+		writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_clr);
+		return mxs_spi_xfer_pio(mxs_slave, data, len, write, flags);
+	} else {
+		writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_set);
+		return mxs_spi_xfer_dma(mxs_slave, data, len, write, flags);
+	}
+}