openwrt/target/linux/brcm63xx/patches-3.8/426-SPI-MIPS-BCM63XX-Add-HS-SPI-driver.patch
Jonas Gorski 8506964e6d bcm63xx: add support for linux 3.8
Based on 3.8-rc6

Signed-off-by: Jonas Gorski <jogo@openwrt.org>

SVN-Revision: 35482
2013-02-04 10:19:55 +00:00

482 lines
12 KiB
Diff

From 4b27423676485d05bcd6fc6f3809164fb8f9d22d Mon Sep 17 00:00:00 2001
From: Jonas Gorski <jonas.gorski@gmail.com>
Date: Sat, 12 Nov 2011 12:19:55 +0100
Subject: [PATCH 30/60] SPI: MIPS: BCM63XX: Add HSSPI driver
Add a driver for the High Speed SPI controller found on newer BCM63XX SoCs.
Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
---
.../include/asm/mach-bcm63xx/bcm63xx_dev_hsspi.h | 2 +
drivers/spi/Kconfig | 7 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-bcm63xx-hsspi.c | 427 ++++++++++++++++++++
4 files changed, 437 insertions(+), 0 deletions(-)
create mode 100644 drivers/spi/spi-bcm63xx-hsspi.c
--- a/arch/mips/include/asm/mach-bcm63xx/bcm63xx_dev_hsspi.h
+++ b/arch/mips/include/asm/mach-bcm63xx/bcm63xx_dev_hsspi.h
@@ -17,4 +17,6 @@ struct bcm63xx_hsspi_pdata {
#define HSSPI_PLL_HZ_6328 133333333
+#define HSSPI_BUFFER_LEN 512
+
#endif /* BCM63XX_DEV_HSSPI_H */
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -100,6 +100,13 @@ config SPI_BCM63XX
help
Enable support for the SPI controller on the Broadcom BCM63xx SoCs.
+config SPI_BCM63XX_HSSPI
+ tristate "Broadcom BCM63XX HS SPI controller driver"
+ depends on BCM63XX
+ help
+ This enables support for the High Speed SPI controller present on
+ newer Broadcom BCM63XX SoCs.
+
config SPI_BITBANG
tristate "Utilities for Bitbanging SPI masters"
help
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_SPI_ATMEL) += spi-atmel.o
obj-$(CONFIG_SPI_ATH79) += spi-ath79.o
obj-$(CONFIG_SPI_AU1550) += spi-au1550.o
obj-$(CONFIG_SPI_BCM63XX) += spi-bcm63xx.o
+obj-$(CONFIG_SPI_BCM63XX_HSSPI) += spi-bcm63xx-hsspi.o
obj-$(CONFIG_SPI_BFIN5XX) += spi-bfin5xx.o
obj-$(CONFIG_SPI_BFIN_SPORT) += spi-bfin-sport.o
obj-$(CONFIG_SPI_BITBANG) += spi-bitbang.o
--- /dev/null
+++ b/drivers/spi/spi-bcm63xx-hsspi.c
@@ -0,0 +1,427 @@
+/*
+ * Broadcom BCM63XX High Speed SPI Controller driver
+ *
+ * Copyright 2000-2010 Broadcom Corporation
+ * Copyright 2012 Jonas Gorski <jonas.gorski@gmail.com>
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/spi/spi.h>
+#include <linux/workqueue.h>
+
+#include <bcm63xx_regs.h>
+#include <bcm63xx_dev_hsspi.h>
+
+#define HSSPI_OP_CODE_SHIFT 13
+#define HSSPI_OP_SLEEP (0 << HSSPI_OP_CODE_SHIFT)
+#define HSSPI_OP_READ_WRITE (1 << HSSPI_OP_CODE_SHIFT)
+#define HSSPI_OP_WRITE (2 << HSSPI_OP_CODE_SHIFT)
+#define HSSPI_OP_READ (3 << HSSPI_OP_CODE_SHIFT)
+
+#define HSSPI_MAX_PREPEND_LEN 15
+
+#define HSSPI_MAX_SYNC_CLOCK 30000000
+
+struct bcm63xx_hsspi {
+ struct completion done;
+ struct spi_transfer *curr_trans;
+
+ struct platform_device *pdev;
+ struct clk *clk;
+ void __iomem *regs;
+ u8 __iomem *fifo;
+
+ u32 speed_hz;
+ int irq;
+};
+
+static void bcm63xx_hsspi_set_clk(struct bcm63xx_hsspi *bs, int hz,
+ int profile)
+{
+ u32 reg;
+
+ reg = DIV_ROUND_UP(2048, DIV_ROUND_UP(bs->speed_hz, hz));
+ bcm_hsspi_writel(CLK_CTRL_ACCUM_RST_ON_LOOP | reg,
+ HSSPI_PROFILE_CLK_CTRL_REG(profile));
+
+ reg = bcm_hsspi_readl(HSSPI_PROFILE_SIGNAL_CTRL_REG(profile));
+ if (hz > HSSPI_MAX_SYNC_CLOCK)
+ reg |= SIGNAL_CTRL_ASYNC_INPUT_PATH;
+ else
+ reg &= ~SIGNAL_CTRL_ASYNC_INPUT_PATH;
+ bcm_hsspi_writel(reg, HSSPI_PROFILE_SIGNAL_CTRL_REG(profile));
+}
+
+static int bcm63xx_hsspi_do_txrx(struct spi_device *spi,
+ struct spi_transfer *t1,
+ struct spi_transfer *t2)
+{
+ struct bcm63xx_hsspi *bs = spi_master_get_devdata(spi->master);
+ u8 chip_select = spi->chip_select;
+ u16 opcode = 0;
+ int len, prepend_size = 0;
+
+ init_completion(&bs->done);
+
+ bs->curr_trans = t2 ? t2 : t1;
+ bcm63xx_hsspi_set_clk(bs, bs->curr_trans->speed_hz, chip_select);
+
+ if (t2 && !t2->tx_buf)
+ prepend_size = t1->len;
+
+ bcm_hsspi_writel(prepend_size << MODE_CTRL_PREPENDBYTE_CNT_SHIFT |
+ 2 << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT |
+ 2 << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT | 0xff,
+ HSSPI_PROFILE_MODE_CTRL_REG(chip_select));
+
+ if (t1->rx_buf && t1->tx_buf)
+ opcode = HSSPI_OP_READ_WRITE;
+ else if (t1->rx_buf || (t2 && t2->rx_buf))
+ opcode = HSSPI_OP_READ;
+ else if (t1->tx_buf)
+ opcode = HSSPI_OP_WRITE;
+
+ if (opcode == HSSPI_OP_READ && t2)
+ len = t2->len;
+ else
+ len = t1->len;
+
+ if (t1->tx_buf) {
+ memcpy_toio(bs->fifo + 2, t1->tx_buf, t1->len);
+ if (t2 && t2->tx_buf) {
+ memcpy_toio(bs->fifo + 2 + t1->len,
+ t2->tx_buf, t2->len);
+ len += t2->len;
+ }
+ }
+
+ opcode |= len;
+ memcpy_toio(bs->fifo, &opcode, sizeof(opcode));
+
+ /* enable interrupt */
+ bcm_hsspi_writel(HSSPI_PING0_CMD_DONE, HSSPI_INT_MASK_REG);
+
+ /* start the transfer */
+ bcm_hsspi_writel(chip_select << PINGPONG_CMD_SS_SHIFT |
+ chip_select << PINGPONG_CMD_PROFILE_SHIFT |
+ PINGPONG_COMMAND_START_NOW,
+ HSSPI_PINGPONG_COMMAND_REG(0));
+
+ if (wait_for_completion_timeout(&bs->done, HZ) == 0) {
+ dev_err(&bs->pdev->dev, "transfer timed out!\n");
+ return -ETIMEDOUT;
+ }
+
+ return t1->len + (t2 ? t2->len : 0);
+}
+
+static int bcm63xx_hsspi_setup(struct spi_device *spi)
+{
+ u32 reg;
+
+ if (spi->bits_per_word != 8)
+ return -EINVAL;
+
+ if (spi->max_speed_hz == 0)
+ return -EINVAL;
+
+ reg = bcm_hsspi_readl(HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select));
+ reg &= ~(SIGNAL_CTRL_LAUNCH_RISING | SIGNAL_CTRL_LATCH_RISING);
+ if (spi->mode & SPI_CPHA)
+ reg |= SIGNAL_CTRL_LAUNCH_RISING;
+ else
+ reg |= SIGNAL_CTRL_LATCH_RISING;
+ bcm_hsspi_writel(reg, HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select));
+
+ return 0;
+}
+
+static int bcm63xx_hsspi_transfer_one(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct spi_transfer *t, *prev = NULL;
+ struct spi_device *spi = msg->spi;
+ u32 reg;
+ int ret = -EINVAL;
+ int len = 0;
+
+ /* check if we are able to make these transfers */
+ list_for_each_entry(t, &msg->transfers, transfer_list) {
+ if (!t->tx_buf && !t->rx_buf)
+ goto out;
+
+ if (t->speed_hz == 0)
+ t->speed_hz = spi->max_speed_hz;
+
+ if (t->speed_hz > spi->max_speed_hz)
+ goto out;
+
+ if (t->len > HSSPI_BUFFER_LEN)
+ goto out;
+
+ /*
+ * This controller does not support keeping the chip select
+ * active between transfers.
+ * This logic currently supports combining:
+ * write then read with no cs_change (e.g. m25p80 RDSR)
+ * write then write with no cs_change (e.g. m25p80 PP)
+ */
+ if (prev && prev->tx_buf && !prev->cs_change && !t->cs_change) {
+ /*
+ * reject if we have to combine two tx transfers and
+ * their combined length is bigger than the buffer
+ */
+ if (prev->tx_buf && t->tx_buf &&
+ (prev->len + t->len) > HSSPI_BUFFER_LEN)
+ goto out;
+ /*
+ * reject if we need write more than 15 bytes in read
+ * then write.
+ */
+ if (prev->tx_buf && t->rx_buf &&
+ prev->len > HSSPI_MAX_PREPEND_LEN)
+ goto out;
+ }
+
+ }
+
+ /* setup clock polarity */
+ reg = bcm_hsspi_readl(HSSPI_GLOBAL_CTRL_REG);
+ reg &= ~GLOBAL_CTRL_CLK_POLARITY;
+ if (spi->mode & SPI_CPOL)
+ reg |= GLOBAL_CTRL_CLK_POLARITY;
+ bcm_hsspi_writel(reg, HSSPI_GLOBAL_CTRL_REG);
+
+ list_for_each_entry(t, &msg->transfers, transfer_list) {
+ if (prev && prev->tx_buf && !prev->cs_change && !t->cs_change) {
+ /* combine write with following transfer */
+ ret = bcm63xx_hsspi_do_txrx(msg->spi, prev, t);
+ if (ret < 0)
+ goto out;
+
+ len += ret;
+ prev = NULL;
+ continue;
+ }
+
+ /* write the previous pending transfer */
+ if (prev != NULL) {
+ ret = bcm63xx_hsspi_do_txrx(msg->spi, prev, NULL);
+ if (ret < 0)
+ goto out;
+
+ len += ret;
+ }
+
+ prev = t;
+ }
+
+ /* do last pending transfer */
+ if (prev != NULL) {
+ ret = bcm63xx_hsspi_do_txrx(msg->spi, prev, NULL);
+ if (ret < 0)
+ goto out;
+ len += ret;
+ }
+
+ msg->actual_length = len;
+ ret = 0;
+out:
+ msg->status = ret;
+ spi_finalize_current_message(master);
+ return 0;
+}
+
+static irqreturn_t bcm63xx_hsspi_interrupt(int irq, void *dev_id)
+{
+ struct spi_master *master = (struct spi_master *)dev_id;
+ struct bcm63xx_hsspi *bs = spi_master_get_devdata(master);
+
+ if (bcm_hsspi_readl(HSSPI_INT_STATUS_MASKED_REG) == 0)
+ return IRQ_NONE;
+
+ bcm_hsspi_writel(HSSPI_INT_CLEAR_ALL, HSSPI_INT_STATUS_REG);
+ bcm_hsspi_writel(0, HSSPI_INT_MASK_REG);
+
+ if (bs->curr_trans && bs->curr_trans->rx_buf)
+ memcpy_fromio(bs->curr_trans->rx_buf, bs->fifo,
+ bs->curr_trans->len);
+ complete(&bs->done);
+
+ return IRQ_HANDLED;
+}
+
+static int bcm63xx_hsspi_probe(struct platform_device *pdev)
+{
+
+ struct spi_master *master;
+ struct bcm63xx_hsspi *bs;
+ struct resource *res_mem;
+ void __iomem *regs;
+ struct device *dev = &pdev->dev;
+ struct bcm63xx_hsspi_pdata *pdata = pdev->dev.platform_data;
+ struct clk *clk;
+ int irq;
+ int ret;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(dev, "no irq\n");
+ return -ENXIO;
+ }
+
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ regs = devm_request_and_ioremap(dev, res_mem);
+ if (!regs) {
+ dev_err(dev, "unable to ioremap regs\n");
+ return -ENXIO;
+ }
+
+ clk = clk_get(dev, "hsspi");
+
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ goto out_release;
+ }
+
+ clk_prepare_enable(clk);
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*bs));
+ if (!master) {
+ ret = -ENOMEM;
+ goto out_disable_clk;
+ }
+
+ bs = spi_master_get_devdata(master);
+ bs->pdev = pdev;
+ bs->clk = clk;
+ bs->regs = regs;
+
+ master->bus_num = pdata->bus_num;
+ master->num_chipselect = 8;
+ master->setup = bcm63xx_hsspi_setup;
+ master->transfer_one_message = bcm63xx_hsspi_transfer_one;
+ master->mode_bits = SPI_CPOL | SPI_CPHA;
+
+ bs->speed_hz = pdata->speed_hz;
+ bs->fifo = (u8 __iomem *)(bs->regs + HSSPI_FIFO_REG(0));
+
+ platform_set_drvdata(pdev, master);
+
+ bs->curr_trans = NULL;
+
+ /* Initialize the hardware */
+ bcm_hsspi_writel(0, HSSPI_INT_MASK_REG);
+
+ /* clean up any pending interrupts */
+ bcm_hsspi_writel(HSSPI_INT_CLEAR_ALL, HSSPI_INT_STATUS_REG);
+
+ bcm_hsspi_writel(bcm_hsspi_readl(HSSPI_GLOBAL_CTRL_REG) |
+ GLOBAL_CTRL_CLK_GATE_SSOFF,
+ HSSPI_GLOBAL_CTRL_REG);
+
+ ret = devm_request_irq(dev, irq, bcm63xx_hsspi_interrupt, IRQF_SHARED,
+ pdev->name, master);
+
+ if (ret)
+ goto out_put_master;
+
+ /* register and we are done */
+ ret = spi_register_master(master);
+ if (ret)
+ goto out_free_irq;
+
+ return 0;
+
+out_free_irq:
+ devm_free_irq(dev, bs->irq, master);
+out_put_master:
+ spi_master_put(master);
+out_disable_clk:
+ clk_disable_unprepare(clk);
+ clk_put(clk);
+out_release:
+ devm_ioremap_release(dev, regs);
+
+ return ret;
+}
+
+
+static int __exit bcm63xx_hsspi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct bcm63xx_hsspi *bs = spi_master_get_devdata(master);
+
+ spi_unregister_master(master);
+
+ /* reset the hardware and block queue progress */
+ bcm_hsspi_writel(0, HSSPI_INT_MASK_REG);
+ clk_disable_unprepare(bs->clk);
+ clk_put(bs->clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int bcm63xx_hsspi_suspend(struct platform_device *pdev,
+ pm_message_t mesg)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct bcm63xx_hsspi *bs = spi_master_get_devdata(master);
+
+ spi_master_suspend(master);
+ clk_disable(bs->clk);
+
+ return 0;
+}
+
+static int bcm63xx_hsspi_resume(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct bcm63xx_hsspi *bs = spi_master_get_devdata(master);
+
+ clk_enable(bs->clk);
+ spi_master_resume(master);
+
+ return 0;
+}
+
+static const struct dev_pm_ops bcm63xx_hsspi_pm_ops = {
+ .suspend = bcm63xx_hsspi_suspend,
+ .resume = bcm63xx_hsspi_resume,
+};
+
+#define BCM63XX_HSSPI_PM_OPS (&bcm63xx_hsspi_pm_ops)
+#else
+#define BCM63XX_HSSPI_PM_OPS NULL
+#endif
+
+
+
+static struct platform_driver bcm63xx_hsspi_driver = {
+ .driver = {
+ .name = "bcm63xx-hsspi",
+ .owner = THIS_MODULE,
+ .pm = BCM63XX_HSSPI_PM_OPS,
+ },
+ .probe = bcm63xx_hsspi_probe,
+ .remove = __exit_p(bcm63xx_hsspi_remove),
+};
+
+module_platform_driver(bcm63xx_hsspi_driver);
+
+MODULE_ALIAS("platform:bcm63xx_hsspi");
+MODULE_DESCRIPTION("Broadcom BCM63xx HS SPI Controller driver");
+MODULE_AUTHOR("Jonas Gorski <jonas.gorski@gmail.com>");
+MODULE_LICENSE("GPL");