add support for mikrotik rb4xx

Signed-off-by: Phil Sutter <phil@nwl.cc>

1 files changed, 557 insertions, 0 deletions

diff --git a/target/mips/mikrotik-rb4xx/patches/3.14.7/0006-spi-add-rb4xx-SPI-driver.patch b/target/mips/mikrotik-rb4xx/patches/3.14.7/0006-spi-add-rb4xx-SPI-driver.patch
new file mode 100644
index 000000000..757dc775b
--- /dev/null
+++ b/target/mips/mikrotik-rb4xx/patches/3.14.7/0006-spi-add-rb4xx-SPI-driver.patch
@@ -0,0 +1,557 @@
+From 97ffc04a7528abe1d84c069d99afb19704d50224 Mon Sep 17 00:00:00 2001
+From: Phil Sutter <phil@nwl.cc>
+Date: Tue, 13 May 2014 00:18:58 +0200
+Subject: [PATCH] spi: add rb4xx SPI driver
+
+---
+ drivers/spi/Kconfig     |   6 +
+ drivers/spi/Makefile    |   1 +
+ drivers/spi/spi-rb4xx.c | 507 ++++++++++++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 514 insertions(+)
+ create mode 100644 drivers/spi/spi-rb4xx.c
+
+diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
+index 581ee2a..721f3a7 100644
+--- a/drivers/spi/Kconfig
++++ b/drivers/spi/Kconfig
+@@ -381,6 +381,12 @@ config SPI_RSPI
+ 	help
+ 	  SPI driver for Renesas RSPI and QSPI blocks.
+ 
++config SPI_RB4XX
++	tristate "Mikrotik RB4XX SPI master"
++	depends on SPI_MASTER && ATH79_MACH_RB4XX
++	help
++	  SPI controller driver for the Mikrotik RB4xx series boards.
++
+ config SPI_S3C24XX
+ 	tristate "Samsung S3C24XX series SPI"
+ 	depends on ARCH_S3C24XX
+diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
+index 95af48d..e738c7a 100644
+--- a/drivers/spi/Makefile
++++ b/drivers/spi/Makefile
+@@ -59,6 +59,7 @@ spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_PXADMA)	+= spi-pxa2xx-pxadma.o
+ spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_DMA)	+= spi-pxa2xx-dma.o
+ obj-$(CONFIG_SPI_PXA2XX)		+= spi-pxa2xx-platform.o
+ obj-$(CONFIG_SPI_PXA2XX_PCI)		+= spi-pxa2xx-pci.o
++obj-$(CONFIG_SPI_RB4XX)			+= spi-rb4xx.o
+ obj-$(CONFIG_SPI_RSPI)			+= spi-rspi.o
+ obj-$(CONFIG_SPI_S3C24XX)		+= spi-s3c24xx-hw.o
+ spi-s3c24xx-hw-y			:= spi-s3c24xx.o
+diff --git a/drivers/spi/spi-rb4xx.c b/drivers/spi/spi-rb4xx.c
+new file mode 100644
+index 0000000..56260ff
+--- /dev/null
++++ b/drivers/spi/spi-rb4xx.c
+@@ -0,0 +1,507 @@
++/*
++ * SPI controller driver for the Mikrotik RB4xx boards
++ *
++ * Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
++ *
++ * This file was based on the patches for Linux 2.6.27.39 published by
++ * MikroTik for their RouterBoard 4xx series devices.
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ *
++ */
++
++#include <linux/clk.h>
++#include <linux/err.h>
++#include <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/init.h>
++#include <linux/delay.h>
++#include <linux/spinlock.h>
++#include <linux/workqueue.h>
++#include <linux/platform_device.h>
++#include <linux/spi/spi.h>
++
++#include <asm/mach-ath79/ar71xx_regs.h>
++#include <asm/mach-ath79/ath79.h>
++
++#define DRV_NAME	"rb4xx-spi"
++#define DRV_DESC	"Mikrotik RB4xx SPI controller driver"
++#define DRV_VERSION	"0.1.0"
++
++#define SPI_CTRL_FASTEST	0x40
++#define SPI_FLASH_HZ		33333334
++#define SPI_CPLD_HZ		33333334
++
++#define CPLD_CMD_READ_FAST	0x0b
++
++#undef RB4XX_SPI_DEBUG
++
++struct rb4xx_spi {
++	void __iomem		*base;
++	struct spi_master	*master;
++
++	unsigned		spi_ctrl_flash;
++	unsigned		spi_ctrl_fread;
++
++	struct clk		*ahb_clk;
++	unsigned long		ahb_freq;
++
++	spinlock_t		lock;
++	struct list_head	queue;
++	int			busy:1;
++	int			cs_wait;
++};
++
++static unsigned spi_clk_low = AR71XX_SPI_IOC_CS1;
++
++#ifdef RB4XX_SPI_DEBUG
++static inline void do_spi_delay(void)
++{
++	ndelay(20000);
++}
++#else
++static inline void do_spi_delay(void) { }
++#endif
++
++static inline void do_spi_init(struct spi_device *spi)
++{
++	unsigned cs = AR71XX_SPI_IOC_CS0 | AR71XX_SPI_IOC_CS1;
++
++	if (!(spi->mode & SPI_CS_HIGH))
++		cs ^= (spi->chip_select == 2) ? AR71XX_SPI_IOC_CS1 :
++						AR71XX_SPI_IOC_CS0;
++
++	spi_clk_low = cs;
++}
++
++static inline void do_spi_finish(void __iomem *base)
++{
++	do_spi_delay();
++	__raw_writel(AR71XX_SPI_IOC_CS0 | AR71XX_SPI_IOC_CS1,
++		     base + AR71XX_SPI_REG_IOC);
++}
++
++static inline void do_spi_clk(void __iomem *base, int bit)
++{
++	unsigned bval = spi_clk_low | ((bit & 1) ? AR71XX_SPI_IOC_DO : 0);
++
++	do_spi_delay();
++	__raw_writel(bval, base + AR71XX_SPI_REG_IOC);
++	do_spi_delay();
++	__raw_writel(bval | AR71XX_SPI_IOC_CLK, base + AR71XX_SPI_REG_IOC);
++}
++
++static void do_spi_byte(void __iomem *base, unsigned char byte)
++{
++	do_spi_clk(base, byte >> 7);
++	do_spi_clk(base, byte >> 6);
++	do_spi_clk(base, byte >> 5);
++	do_spi_clk(base, byte >> 4);
++	do_spi_clk(base, byte >> 3);
++	do_spi_clk(base, byte >> 2);
++	do_spi_clk(base, byte >> 1);
++	do_spi_clk(base, byte);
++
++	pr_debug("spi_byte sent 0x%02x got 0x%02x\n",
++	       (unsigned)byte,
++	       (unsigned char)__raw_readl(base + AR71XX_SPI_REG_RDS));
++}
++
++static inline void do_spi_clk_fast(void __iomem *base, unsigned bit1,
++				   unsigned bit2)
++{
++	unsigned bval = (spi_clk_low |
++			 ((bit1 & 1) ? AR71XX_SPI_IOC_DO : 0) |
++			 ((bit2 & 1) ? AR71XX_SPI_IOC_CS2 : 0));
++	do_spi_delay();
++	__raw_writel(bval, base + AR71XX_SPI_REG_IOC);
++	do_spi_delay();
++	__raw_writel(bval | AR71XX_SPI_IOC_CLK, base + AR71XX_SPI_REG_IOC);
++}
++
++static void do_spi_byte_fast(void __iomem *base, unsigned char byte)
++{
++	do_spi_clk_fast(base, byte >> 7, byte >> 6);
++	do_spi_clk_fast(base, byte >> 5, byte >> 4);
++	do_spi_clk_fast(base, byte >> 3, byte >> 2);
++	do_spi_clk_fast(base, byte >> 1, byte >> 0);
++
++	pr_debug("spi_byte_fast sent 0x%02x got 0x%02x\n",
++	       (unsigned)byte,
++	       (unsigned char) __raw_readl(base + AR71XX_SPI_REG_RDS));
++}
++
++static int rb4xx_spi_txrx(void __iomem *base, struct spi_transfer *t)
++{
++	const unsigned char *rxv_ptr = NULL;
++	const unsigned char *tx_ptr = t->tx_buf;
++	unsigned char *rx_ptr = t->rx_buf;
++	unsigned i;
++
++	pr_debug("spi_txrx len %u tx %u rx %u\n",
++	       t->len,
++	       (t->tx_buf ? 1 : 0),
++	       (t->rx_buf ? 1 : 0));
++
++	if (t->verify) {
++		rxv_ptr = tx_ptr;
++		tx_ptr = NULL;
++	}
++
++	for (i = 0; i < t->len; ++i) {
++		unsigned char sdata = tx_ptr ? tx_ptr[i] : 0;
++
++		if (t->fast_write)
++			do_spi_byte_fast(base, sdata);
++		else
++			do_spi_byte(base, sdata);
++
++		if (rx_ptr) {
++			rx_ptr[i] = __raw_readl(base + AR71XX_SPI_REG_RDS) & 0xff;
++		} else if (rxv_ptr) {
++			unsigned char c = __raw_readl(base + AR71XX_SPI_REG_RDS);
++			if (rxv_ptr[i] != c)
++				return i;
++		}
++	}
++
++	return i;
++}
++
++static int rb4xx_spi_read_fast(struct rb4xx_spi *rbspi,
++			       struct spi_message *m)
++{
++	struct spi_transfer *t;
++	const unsigned char *tx_ptr;
++	unsigned addr;
++	void __iomem *base = rbspi->base;
++
++	/* check for exactly two transfers */
++	if (list_empty(&m->transfers) ||
++	    list_is_last(m->transfers.next, &m->transfers) ||
++	    !list_is_last(m->transfers.next->next, &m->transfers)) {
++		return -1;
++	}
++
++	/* first transfer contains command and address  */
++	t = list_entry(m->transfers.next,
++		       struct spi_transfer, transfer_list);
++
++	if (t->len != 5 || t->tx_buf == NULL)
++		return -1;
++
++	tx_ptr = t->tx_buf;
++	if (tx_ptr[0] != CPLD_CMD_READ_FAST)
++		return -1;
++
++	addr = tx_ptr[1];
++	addr = tx_ptr[2] | (addr << 8);
++	addr = tx_ptr[3] | (addr << 8);
++	addr += (unsigned) base;
++
++	m->actual_length += t->len;
++
++	/* second transfer contains data itself */
++	t = list_entry(m->transfers.next->next,
++		       struct spi_transfer, transfer_list);
++
++	if (t->tx_buf && !t->verify)
++		return -1;
++
++	__raw_writel(AR71XX_SPI_FS_GPIO, base + AR71XX_SPI_REG_FS);
++	__raw_writel(rbspi->spi_ctrl_fread, base + AR71XX_SPI_REG_CTRL);
++	__raw_writel(0, base + AR71XX_SPI_REG_FS);
++
++	if (t->rx_buf) {
++		memcpy(t->rx_buf, (const void *)addr, t->len);
++	} else if (t->tx_buf) {
++		unsigned char buf[t->len];
++		memcpy(buf, (const void *)addr, t->len);
++		if (memcmp(t->tx_buf, buf, t->len) != 0)
++			m->status = -EMSGSIZE;
++	}
++	m->actual_length += t->len;
++
++	if (rbspi->spi_ctrl_flash != rbspi->spi_ctrl_fread) {
++		__raw_writel(AR71XX_SPI_FS_GPIO, base + AR71XX_SPI_REG_FS);
++		__raw_writel(rbspi->spi_ctrl_flash, base + AR71XX_SPI_REG_CTRL);
++		__raw_writel(0, base + AR71XX_SPI_REG_FS);
++	}
++
++	return 0;
++}
++
++static int rb4xx_spi_msg(struct rb4xx_spi *rbspi, struct spi_message *m)
++{
++	struct spi_transfer *t = NULL;
++	void __iomem *base = rbspi->base;
++
++	m->status = 0;
++	if (list_empty(&m->transfers))
++		return -1;
++
++	if (m->fast_read)
++		if (rb4xx_spi_read_fast(rbspi, m) == 0)
++			return -1;
++
++	__raw_writel(AR71XX_SPI_FS_GPIO, base + AR71XX_SPI_REG_FS);
++	__raw_writel(SPI_CTRL_FASTEST, base + AR71XX_SPI_REG_CTRL);
++	do_spi_init(m->spi);
++
++	list_for_each_entry(t, &m->transfers, transfer_list) {
++		int len;
++
++		len = rb4xx_spi_txrx(base, t);
++		if (len != t->len) {
++			m->status = -EMSGSIZE;
++			break;
++		}
++		m->actual_length += len;
++
++		if (t->cs_change) {
++			if (list_is_last(&t->transfer_list, &m->transfers)) {
++				/* wait for continuation */
++				return m->spi->chip_select;
++			}
++			do_spi_finish(base);
++			ndelay(100);
++		}
++	}
++
++	do_spi_finish(base);
++	__raw_writel(rbspi->spi_ctrl_flash, base + AR71XX_SPI_REG_CTRL);
++	__raw_writel(0, base + AR71XX_SPI_REG_FS);
++	return -1;
++}
++
++static void rb4xx_spi_process_queue_locked(struct rb4xx_spi *rbspi,
++					   unsigned long *flags)
++{
++	int cs = rbspi->cs_wait;
++
++	rbspi->busy = 1;
++	while (!list_empty(&rbspi->queue)) {
++		struct spi_message *m;
++
++		list_for_each_entry(m, &rbspi->queue, queue)
++			if (cs < 0 || cs == m->spi->chip_select)
++				break;
++
++		if (&m->queue == &rbspi->queue)
++			break;
++
++		list_del_init(&m->queue);
++		spin_unlock_irqrestore(&rbspi->lock, *flags);
++
++		cs = rb4xx_spi_msg(rbspi, m);
++		m->complete(m->context);
++
++		spin_lock_irqsave(&rbspi->lock, *flags);
++	}
++
++	rbspi->cs_wait = cs;
++	rbspi->busy = 0;
++
++	if (cs >= 0) {
++		/* TODO: add timer to unlock cs after 1s inactivity */
++	}
++}
++
++static int rb4xx_spi_transfer(struct spi_device *spi,
++			      struct spi_message *m)
++{
++	struct rb4xx_spi *rbspi = spi_master_get_devdata(spi->master);
++	unsigned long flags;
++
++	m->actual_length = 0;
++	m->status = -EINPROGRESS;
++
++	spin_lock_irqsave(&rbspi->lock, flags);
++	list_add_tail(&m->queue, &rbspi->queue);
++	if (rbspi->busy ||
++	    (rbspi->cs_wait >= 0 && rbspi->cs_wait != m->spi->chip_select)) {
++		/* job will be done later */
++		spin_unlock_irqrestore(&rbspi->lock, flags);
++		return 0;
++	}
++
++	/* process job in current context */
++	rb4xx_spi_process_queue_locked(rbspi, &flags);
++	spin_unlock_irqrestore(&rbspi->lock, flags);
++
++	return 0;
++}
++
++static int rb4xx_spi_setup(struct spi_device *spi)
++{
++	struct rb4xx_spi *rbspi = spi_master_get_devdata(spi->master);
++	unsigned long flags;
++
++	if (spi->mode & ~(SPI_CS_HIGH)) {
++		dev_err(&spi->dev, "mode %x not supported\n",
++			(unsigned) spi->mode);
++		return -EINVAL;
++	}
++
++	if (spi->bits_per_word != 8 && spi->bits_per_word != 0) {
++		dev_err(&spi->dev, "bits_per_word %u not supported\n",
++			(unsigned) spi->bits_per_word);
++		return -EINVAL;
++	}
++
++	spin_lock_irqsave(&rbspi->lock, flags);
++	if (rbspi->cs_wait == spi->chip_select && !rbspi->busy) {
++		rbspi->cs_wait = -1;
++		rb4xx_spi_process_queue_locked(rbspi, &flags);
++	}
++	spin_unlock_irqrestore(&rbspi->lock, flags);
++
++	return 0;
++}
++
++static unsigned get_spi_ctrl(struct rb4xx_spi *rbspi, unsigned hz_max,
++			     const char *name)
++{
++	unsigned div;
++
++	div = (rbspi->ahb_freq - 1) / (2 * hz_max);
++
++	/*
++	 * CPU has a bug at (div == 0) - first bit read is random
++	 */
++	if (div == 0)
++		++div;
++
++	if (name) {
++		unsigned ahb_khz = (rbspi->ahb_freq + 500) / 1000;
++		unsigned div_real = 2 * (div + 1);
++		pr_debug("rb4xx: %s SPI clock %u kHz (AHB %u kHz / %u)\n",
++		       name,
++		       ahb_khz / div_real,
++		       ahb_khz, div_real);
++	}
++
++	return SPI_CTRL_FASTEST + div;
++}
++
++static int rb4xx_spi_probe(struct platform_device *pdev)
++{
++	struct spi_master *master;
++	struct rb4xx_spi *rbspi;
++	struct resource *r;
++	int err = 0;
++
++	master = spi_alloc_master(&pdev->dev, sizeof(*rbspi));
++	if (master == NULL) {
++		dev_err(&pdev->dev, "no memory for spi_master\n");
++		err = -ENOMEM;
++		goto err_out;
++	}
++
++	master->bus_num = 0;
++	master->num_chipselect = 3;
++	master->setup = rb4xx_spi_setup;
++	master->transfer = rb4xx_spi_transfer;
++
++	rbspi = spi_master_get_devdata(master);
++
++	rbspi->ahb_clk = clk_get(&pdev->dev, "ahb");
++	if (IS_ERR(rbspi->ahb_clk)) {
++		err = PTR_ERR(rbspi->ahb_clk);
++		goto err_put_master;
++	}
++
++	err = clk_enable(rbspi->ahb_clk);
++	if (err)
++		goto err_clk_put;
++
++	rbspi->ahb_freq = clk_get_rate(rbspi->ahb_clk);
++	if (!rbspi->ahb_freq) {
++		err = -EINVAL;
++		goto err_clk_disable;
++	}
++
++	platform_set_drvdata(pdev, rbspi);
++
++	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++	if (r == NULL) {
++		err = -ENOENT;
++		goto err_clk_disable;
++	}
++
++	rbspi->base = ioremap(r->start, r->end - r->start + 1);
++	if (!rbspi->base) {
++		err = -ENXIO;
++		goto err_clk_disable;
++	}
++
++	rbspi->master = master;
++	rbspi->spi_ctrl_flash = get_spi_ctrl(rbspi, SPI_FLASH_HZ, "FLASH");
++	rbspi->spi_ctrl_fread = get_spi_ctrl(rbspi, SPI_CPLD_HZ, "CPLD");
++	rbspi->cs_wait = -1;
++
++	spin_lock_init(&rbspi->lock);
++	INIT_LIST_HEAD(&rbspi->queue);
++
++	err = spi_register_master(master);
++	if (err) {
++		dev_err(&pdev->dev, "failed to register SPI master\n");
++		goto err_iounmap;
++	}
++
++	return 0;
++
++err_iounmap:
++	iounmap(rbspi->base);
++err_clk_disable:
++	clk_disable(rbspi->ahb_clk);
++err_clk_put:
++	clk_put(rbspi->ahb_clk);
++err_put_master:
++	platform_set_drvdata(pdev, NULL);
++	spi_master_put(master);
++err_out:
++	return err;
++}
++
++static int rb4xx_spi_remove(struct platform_device *pdev)
++{
++	struct rb4xx_spi *rbspi = platform_get_drvdata(pdev);
++
++	iounmap(rbspi->base);
++	clk_disable(rbspi->ahb_clk);
++	clk_put(rbspi->ahb_clk);
++	platform_set_drvdata(pdev, NULL);
++	spi_master_put(rbspi->master);
++
++	return 0;
++}
++
++static struct platform_driver rb4xx_spi_drv = {
++	.probe		= rb4xx_spi_probe,
++	.remove		= rb4xx_spi_remove,
++	.driver		= {
++		.name	= DRV_NAME,
++		.owner	= THIS_MODULE,
++	},
++};
++
++static int __init rb4xx_spi_init(void)
++{
++	return platform_driver_register(&rb4xx_spi_drv);
++}
++subsys_initcall(rb4xx_spi_init);
++
++static void __exit rb4xx_spi_exit(void)
++{
++	platform_driver_unregister(&rb4xx_spi_drv);
++}
++
++module_exit(rb4xx_spi_exit);
++
++MODULE_DESCRIPTION(DRV_DESC);
++MODULE_VERSION(DRV_VERSION);
++MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
++MODULE_LICENSE("GPL v2");
+-- 
+1.8.5.3
+