[PATCH] ide: Add tx4939ide driver (v5)

[PATCH] ide: Add tx4939ide driver (v5)

[Atsushi Nemoto]

This is the driver for the Toshiba TX4939 SoC ATA controller.

This controller has standard ATA taskfile registers and DMA
command/status registers, but the register layout is swapped on big
endian.  There are some other endian issue and some special registers
which requires many custom dma_ops/tp_ops routines and build_dmatable.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
---
This patch is against current linux-mips tree.

Changes since v4:
* do not select IDE_TIMINGS
* remove unneeded BUG_ON
* use ATA_DMA_XXX symbols
* refactor tx4939ide_tf_load and tx4939ide_tf_load_fixup
* call devm_request_mem_region
* some whitespace and spelling fixes

 drivers/ide/Kconfig          |    5 +
 drivers/ide/mips/Makefile    |    1 +
 drivers/ide/mips/tx4939ide.c |  756 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 762 insertions(+), 0 deletions(-)
 create mode 100644 drivers/ide/mips/tx4939ide.c

diff --git a/drivers/ide/Kconfig b/drivers/ide/Kconfig
index 74a369a..1f0eeba 100644
--- a/drivers/ide/Kconfig
+++ b/drivers/ide/Kconfig
@@ -746,6 +746,11 @@ config BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ
        default "128"
        depends on BLK_DEV_IDE_AU1XXX
 
+config BLK_DEV_IDE_TX4939
+	tristate "TX4939 internal IDE support"
+	depends on SOC_TX4939
+	select BLK_DEV_IDEDMA_SFF
+
 config IDE_ARM
 	tristate "ARM IDE support"
 	depends on ARM && (ARCH_CLPS7500 || ARCH_RPC || ARCH_SHARK)
diff --git a/drivers/ide/mips/Makefile b/drivers/ide/mips/Makefile
index 5873fa0..04e5d86 100644
--- a/drivers/ide/mips/Makefile
+++ b/drivers/ide/mips/Makefile
@@ -1,3 +1,4 @@
 obj-$(CONFIG_BLK_DEV_IDE_AU1XXX)	+= au1xxx-ide.o
 
+obj-$(CONFIG_BLK_DEV_IDE_TX4939)	+= tx4939ide.o
 EXTRA_CFLAGS    := -Idrivers/ide
diff --git a/drivers/ide/mips/tx4939ide.c b/drivers/ide/mips/tx4939ide.c
new file mode 100644
index 0000000..9a42f83
--- /dev/null
+++ b/drivers/ide/mips/tx4939ide.c
@@ -0,0 +1,756 @@
+/*
+ * TX4939 internal IDE driver
+ * Based on RBTX49xx patch from CELF patch archive.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * (C) Copyright TOSHIBA CORPORATION 2005-2007
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/ide.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/scatterlist.h>
+
+#define MODNAME	"tx4939ide"
+
+/* ATA Shadow Registers (8-bit except for Data which is 16-bit) */
+#define TX4939IDE_Data			0x000
+#define TX4939IDE_Error_Feature		0x001
+#define TX4939IDE_Sec			0x002
+#define TX4939IDE_LBA0			0x003
+#define TX4939IDE_LBA1			0x004
+#define TX4939IDE_LBA2			0x005
+#define TX4939IDE_DevHead		0x006
+#define TX4939IDE_Stat_Cmd		0x007
+#define TX4939IDE_AltStat_DevCtl	0x402
+/* H/W DMA Registers  */
+#define TX4939IDE_DMA_Cmd	0x800	/* 8-bit */
+#define TX4939IDE_DMA_Stat	0x802	/* 8-bit */
+#define TX4939IDE_PRD_Ptr	0x804	/* 32-bit */
+/* ATA100 CORE Registers (16-bit) */
+#define TX4939IDE_Sys_Ctl	0xc00
+#define TX4939IDE_Xfer_Cnt_1	0xc08
+#define TX4939IDE_Xfer_Cnt_2	0xc0a
+#define TX4939IDE_Sec_Cnt	0xc10
+#define TX4939IDE_Start_Lo_Addr	0xc18
+#define TX4939IDE_Start_Up_Addr	0xc20
+#define TX4939IDE_Add_Ctl	0xc28
+#define TX4939IDE_Lo_Burst_Cnt	0xc30
+#define TX4939IDE_Up_Burst_Cnt	0xc38
+#define TX4939IDE_PIO_Addr	0xc88
+#define TX4939IDE_H_Rst_Tim	0xc90
+#define TX4939IDE_Int_Ctl	0xc98
+#define TX4939IDE_Pkt_Cmd	0xcb8
+#define TX4939IDE_Bxfer_Cnt_Hi	0xcc0
+#define TX4939IDE_Bxfer_Cnt_Lo	0xcc8
+#define TX4939IDE_Dev_TErr	0xcd0
+#define TX4939IDE_Pkt_Xfer_Ctl	0xcd8
+#define TX4939IDE_Start_TAddr	0xce0
+
+/* bits for Int_Ctl */
+#define TX4939IDE_INT_ADDRERR	0x80
+#define TX4939IDE_INT_REACHMUL	0x40
+#define TX4939IDE_INT_DEVTIMING	0x20
+#define TX4939IDE_INT_UDMATERM	0x10
+#define TX4939IDE_INT_TIMER	0x08
+#define TX4939IDE_INT_BUSERR	0x04
+#define TX4939IDE_INT_XFEREND	0x02
+#define TX4939IDE_INT_HOST	0x01
+
+#define TX4939IDE_IGNORE_INTS	\
+	(TX4939IDE_INT_ADDRERR | TX4939IDE_INT_REACHMUL | \
+	 TX4939IDE_INT_DEVTIMING | TX4939IDE_INT_UDMATERM | \
+	 TX4939IDE_INT_TIMER | TX4939IDE_INT_XFEREND)
+
+#ifdef __BIG_ENDIAN
+#define tx4939ide_swizzlel(a)	((a) ^ 4)
+#define tx4939ide_swizzlew(a)	((a) ^ 6)
+#define tx4939ide_swizzleb(a)	((a) ^ 7)
+#else
+#define tx4939ide_swizzlel(a)	(a)
+#define tx4939ide_swizzlew(a)	(a)
+#define tx4939ide_swizzleb(a)	(a)
+#endif
+
+static u16 tx4939ide_readw(void __iomem *base, u32 reg)
+{
+	return __raw_readw(base + tx4939ide_swizzlew(reg));
+}
+static u8 tx4939ide_readb(void __iomem *base, u32 reg)
+{
+	return __raw_readb(base + tx4939ide_swizzleb(reg));
+}
+static void tx4939ide_writel(u32 val, void __iomem *base, u32 reg)
+{
+	__raw_writel(val, base + tx4939ide_swizzlel(reg));
+}
+static void tx4939ide_writew(u16 val, void __iomem *base, u32 reg)
+{
+	__raw_writew(val, base + tx4939ide_swizzlew(reg));
+}
+static void tx4939ide_writeb(u8 val, void __iomem *base, u32 reg)
+{
+	__raw_writeb(val, base + tx4939ide_swizzleb(reg));
+}
+
+#define TX4939IDE_BASE(hwif)	((void __iomem *)(hwif)->extra_base)
+
+static void tx4939ide_set_pio_mode(ide_drive_t *drive, const u8 pio)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	int is_slave = drive->dn & 1;
+	u32 mask, val;
+	u8 safe = pio;
+	ide_drive_t *pair;
+
+	pair = ide_get_pair_dev(drive);
+	if (pair)
+		safe = min(safe, ide_get_best_pio_mode(pair, 255, 4));
+	/*
+	 * Update Command Transfer Mode for master/slave and Data
+	 * Transfer Mode for this drive.
+	 */
+	mask = is_slave ? 0x07f00000 : 0x000007f0;
+	val = ((safe << 8) | (pio << 4)) << (is_slave ? 16 : 0);
+	hwif->select_data = (hwif->select_data & ~mask) | val;
+	/* tx4939ide_tf_load_fixup() will set the Sys_Ctl register */
+}
+
+static void tx4939ide_set_dma_mode(ide_drive_t *drive, const u8 mode)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	u32 mask, val;
+
+	/* Update Data Transfer Mode for this drive. */
+	if (mode >= XFER_UDMA_0)
+		val = mode - XFER_UDMA_0 + 8;
+	else
+		val = mode - XFER_MW_DMA_0 + 5;
+	if (drive->dn & 1) {
+		mask = 0x00f00000;
+		val <<= 20;
+	} else {
+		mask = 0x000000f0;
+		val <<= 4;
+	}
+	hwif->select_data = (hwif->select_data & ~mask) | val;
+	/* tx4939ide_tf_load_fixup() will set the Sys_Ctl register */
+}
+
+static u16 tx4939ide_check_error_ints(ide_hwif_t *hwif)
+{
+	void __iomem *base = TX4939IDE_BASE(hwif);
+	u16 ctl = tx4939ide_readw(base, TX4939IDE_Int_Ctl);
+
+	if (ctl & TX4939IDE_INT_BUSERR) {
+		/* reset FIFO */
+		u16 sysctl = tx4939ide_readw(base, TX4939IDE_Sys_Ctl);
+		tx4939ide_writew(sysctl | 0x4000, base, TX4939IDE_Sys_Ctl);
+		mmiowb();
+		/* wait 12GBUSCLK (typ. 60ns @ GBUS200MHz, max 270ns) */
+		ndelay(270);
+		tx4939ide_writew(sysctl, base, TX4939IDE_Sys_Ctl);
+	}
+	if (ctl & (TX4939IDE_INT_ADDRERR |
+		   TX4939IDE_INT_DEVTIMING | TX4939IDE_INT_BUSERR))
+		pr_err("%s: Error interrupt %#x (%s%s%s )\n",
+		       hwif->name, ctl,
+		       (ctl & TX4939IDE_INT_ADDRERR) ?
+		       " Address-Error" : "",
+		       (ctl & TX4939IDE_INT_DEVTIMING) ?
+		       " DEV-Timing" : "",
+		       (ctl & TX4939IDE_INT_BUSERR) ?
+		       " Bus-Error" : "");
+	return ctl;
+}
+
+static void tx4939ide_clear_irq(ide_drive_t *drive)
+{
+	ide_hwif_t *hwif;
+	void __iomem *base;
+	u16 ctl;
+
+	/*
+	 * tx4939ide_dma_test_irq() and tx4939ide_dma_end() do all job
+	 * for DMA case.
+	 */
+	if (drive->waiting_for_dma)
+		return;
+	hwif = drive->hwif;
+	base = TX4939IDE_BASE(hwif);
+	ctl = tx4939ide_check_error_ints(hwif);
+	tx4939ide_writew(ctl, base, TX4939IDE_Int_Ctl);
+}
+
+static u8 tx4939ide_cable_detect(ide_hwif_t *hwif)
+{
+	void __iomem *base = TX4939IDE_BASE(hwif);
+
+	return (tx4939ide_readw(base, TX4939IDE_Sys_Ctl) & 0x2000) ?
+		ATA_CBL_PATA40 : ATA_CBL_PATA80;
+}
+
+#ifdef __BIG_ENDIAN
+static void tx4939ide_dma_host_set(ide_drive_t *drive, int on)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	u8 unit = drive->dn & 1;
+	void __iomem *base = TX4939IDE_BASE(hwif);
+	u8 dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
+
+	if (on)
+		dma_stat |= (1 << (5 + unit));
+	else
+		dma_stat &= ~(1 << (5 + unit));
+
+	tx4939ide_writeb(dma_stat, base, TX4939IDE_DMA_Stat);
+}
+#else
+#define tx4939ide_dma_host_set	ide_dma_host_set
+#endif
+
+static u8 tx4939ide_clear_dma_status(void __iomem *base)
+{
+	u8 dma_stat;
+
+	/* read DMA status for INTR & ERROR flags */
+	dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
+	/* clear INTR & ERROR flags */
+	tx4939ide_writeb(dma_stat | 6, base, TX4939IDE_DMA_Stat);
+	/* recover intmask cleared by writing to bit2 of DMA_Stat */
+	tx4939ide_writew(TX4939IDE_IGNORE_INTS << 8, base, TX4939IDE_Int_Ctl);
+	return dma_stat;
+}
+
+#ifdef __BIG_ENDIAN
+/* custom ide_build_dmatable to handle swapped layout */
+static int tx4939ide_build_dmatable(ide_drive_t *drive, struct request *rq)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	u32 *table = (u32 *)hwif->dmatable_cpu;
+	unsigned int count = 0;
+	int i;
+	struct scatterlist *sg;
+
+	hwif->sg_nents = ide_build_sglist(drive, rq);
+	if (hwif->sg_nents == 0)
+		return 0;
+
+	for_each_sg(hwif->sg_table, sg, hwif->sg_nents, i) {
+		u32 cur_addr, cur_len, bcount;
+
+		cur_addr = sg_dma_address(sg);
+		cur_len = sg_dma_len(sg);
+
+		/*
+		 * Fill in the dma table, without crossing any 64kB boundaries.
+		 */
+
+		while (cur_len) {
+			if (count++ >= PRD_ENTRIES)
+				goto use_pio_instead;
+
+			bcount = 0x10000 - (cur_addr & 0xffff);
+			if (bcount > cur_len)
+				bcount = cur_len;
+			*table++ = bcount & 0xffff;
+			*table++ = cur_addr;
+			cur_addr += bcount;
+			cur_len -= bcount;
+		}
+	}
+
+	if (count) {
+		*(table - 2) |= 0x80000000;
+		return count;
+	}
+
+use_pio_instead:
+	printk(KERN_ERR "%s: %s\n", drive->name,
+		count ? "DMA table too small" : "empty DMA table?");
+
+	ide_destroy_dmatable(drive);
+
+	return 0; /* revert to PIO for this request */
+}
+#else
+#define tx4939ide_build_dmatable	ide_build_dmatable
+#endif
+
+static int tx4939ide_dma_setup(ide_drive_t *drive)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	void __iomem *base = TX4939IDE_BASE(hwif);
+	struct request *rq = hwif->hwgroup->rq;
+	u8 reading;
+	int nent;
+
+	if (rq_data_dir(rq))
+		reading = 0;
+	else
+		reading = ATA_DMA_WR;
+
+	/* fall back to pio! */
+	nent = tx4939ide_build_dmatable(drive, rq);
+	if (!nent) {
+		ide_map_sg(drive, rq);
+		return 1;
+	}
+
+	/* PRD table */
+	tx4939ide_writel(hwif->dmatable_dma, base, TX4939IDE_PRD_Ptr);
+
+	/* specify r/w */
+	tx4939ide_writeb(reading, base, TX4939IDE_DMA_Cmd);
+
+	/* clear INTR & ERROR flags */
+	tx4939ide_clear_dma_status(base);
+
+	drive->waiting_for_dma = 1;
+
+	tx4939ide_writew(SECTOR_SIZE / 2, base, (drive->dn & 1) ?
+			 TX4939IDE_Xfer_Cnt_2 : TX4939IDE_Xfer_Cnt_1);
+	tx4939ide_writew(rq->nr_sectors, base, TX4939IDE_Sec_Cnt);
+	return 0;
+}
+
+static int tx4939ide_dma_end(ide_drive_t *drive)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	u8 dma_stat, dma_cmd;
+	void __iomem *base = TX4939IDE_BASE(hwif);
+	u16 ctl = tx4939ide_readw(base, TX4939IDE_Int_Ctl);
+
+	drive->waiting_for_dma = 0;
+
+	/* get DMA command mode */
+	dma_cmd = tx4939ide_readb(base, TX4939IDE_DMA_Cmd);
+	/* stop DMA */
+	tx4939ide_writeb(dma_cmd & ~ATA_DMA_START, base, TX4939IDE_DMA_Cmd);
+
+	/* read and clear the INTR & ERROR bits */
+	dma_stat = tx4939ide_clear_dma_status(base);
+
+	/* purge DMA mappings */
+	ide_destroy_dmatable(drive);
+	/* verify good DMA status */
+	wmb();
+
+	if ((dma_stat & (ATA_DMA_INTR | ATA_DMA_ERR | ATA_DMA_ACTIVE)) == 0 &&
+	    (ctl & (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST)) ==
+	    (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST))
+		/* INT_IDE lost... bug? */
+		return 0;
+	return ((dma_stat & (ATA_DMA_INTR | ATA_DMA_ERR | ATA_DMA_ACTIVE)) !=
+		ATA_DMA_INTR) ? (0x10 | dma_stat) : 0;
+}
+
+/* returns 1 if DMA IRQ issued, 0 otherwise */
+static int tx4939ide_dma_test_irq(ide_drive_t *drive)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	void __iomem *base = TX4939IDE_BASE(hwif);
+	u16 ctl;
+	u8 dma_stat, stat;
+	u16 ide_int;
+	int found = 0;
+
+	ctl = tx4939ide_check_error_ints(hwif);
+	ide_int = ctl & (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST);
+	switch (ide_int) {
+	case TX4939IDE_INT_HOST:
+		/* On error, XFEREND might not be asserted. */
+		stat = tx4939ide_readb(base, TX4939IDE_AltStat_DevCtl);
+		if ((stat & (ATA_BUSY | ATA_DRQ | ATA_ERR)) == ATA_ERR)
+			found = 1;
+		else
+			/* Wait for XFEREND (Mask HOST and unmask XFEREND) */
+			ctl &= ~TX4939IDE_INT_XFEREND << 8;
+		ctl |= ide_int << 8;
+		break;
+	case TX4939IDE_INT_HOST | TX4939IDE_INT_XFEREND:
+		dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
+		if (!(dma_stat & ATA_DMA_INTR))
+			pr_warning("%s: weird interrupt status. "
+				   "DMA_Stat %#02x int_ctl %#04x\n",
+				   hwif->name, dma_stat, ctl);
+		found = 1;
+		break;
+	}
+	/*
+	 * Do not clear XFEREND, HOST now.  They will be cleared by
+	 * clearing bit2 of DMA_Stat.
+	 */
+	ctl &= ~ide_int;
+	tx4939ide_writew(ctl, base, TX4939IDE_Int_Ctl);
+	return found;
+}
+
+static void tx4939ide_init_hwif(ide_hwif_t *hwif)
+{
+	void __iomem *base = TX4939IDE_BASE(hwif);
+
+	/* Soft Reset */
+	tx4939ide_writew(0x8000, base, TX4939IDE_Sys_Ctl);
+	mmiowb();
+	/* at least 20 GBUSCLK (typ. 100ns @ GBUS200MHz, max 450ns) */
+	ndelay(450);
+	tx4939ide_writew(0x0000, base, TX4939IDE_Sys_Ctl);
+	/* mask some interrupts and clear all interrupts */
+	tx4939ide_writew((TX4939IDE_IGNORE_INTS << 8) | 0xff, base,
+			 TX4939IDE_Int_Ctl);
+
+	tx4939ide_writew(0x0008, base, TX4939IDE_Lo_Burst_Cnt);
+	tx4939ide_writew(0, base, TX4939IDE_Up_Burst_Cnt);
+}
+
+static int tx4939ide_init_dma(ide_hwif_t *hwif, const struct ide_port_info *d)
+{
+	hwif->dma_base = hwif->extra_base +
+		tx4939ide_swizzleb(TX4939IDE_DMA_Cmd);
+	/*
+	 * Note that we cannot use ATA_DMA_TABLE_OFS,ATA_DMA_STATUS
+	 * for big endian.
+	 */
+	return ide_allocate_dma_engine(hwif);
+}
+
+static void tx4939ide_tf_load_fixup(ide_drive_t *drive, ide_task_t *task)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	void __iomem *base = TX4939IDE_BASE(hwif);
+	u16 sysctl = hwif->select_data >> ((drive->dn & 1) ? 16 : 0);
+
+	/*
+	 * Fix ATA100 CORE System Control Register. (The write to the
+	 * Device/Head register may write wrong data to the System
+	 * Control Register)
+	 * While Sys_Ctl is written here, selectproc is not needed.
+	 */
+	tx4939ide_writew(sysctl, base, TX4939IDE_Sys_Ctl);
+}
+
+#ifdef __BIG_ENDIAN
+
+static u8 tx4939ide_read_sff_dma_status(ide_hwif_t *hwif)
+{
+	void __iomem *base = TX4939IDE_BASE(hwif);
+
+	return tx4939ide_readb(base, TX4939IDE_DMA_Stat);
+}
+
+/* custom iops (independent from SWAP_IO_SPACE) */
+static u8 tx4939ide_inb(unsigned long port)
+{
+	return __raw_readb((void __iomem *)port);
+}
+
+static void tx4939ide_outb(u8 value, unsigned long port)
+{
+	__raw_writeb(value, (void __iomem *)port);
+}
+
+static void tx4939ide_tf_load(ide_drive_t *drive, ide_task_t *task)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	struct ide_io_ports *io_ports = &hwif->io_ports;
+	struct ide_taskfile *tf = &task->tf;
+	u8 HIHI = (task->tf_flags & IDE_TFLAG_LBA48) ? 0xE0 : 0xEF;
+
+	if (task->tf_flags & IDE_TFLAG_FLAGGED)
+		HIHI = 0xFF;
+
+	if (task->tf_flags & IDE_TFLAG_OUT_DATA) {
+		u16 data = (tf->hob_data << 8) | tf->data;
+
+		/* no endian swap */
+		__raw_writew(data, (void __iomem *)io_ports->data_addr);
+	}
+
+	if (task->tf_flags & IDE_TFLAG_OUT_HOB_FEATURE)
+		tx4939ide_outb(tf->hob_feature, io_ports->feature_addr);
+	if (task->tf_flags & IDE_TFLAG_OUT_HOB_NSECT)
+		tx4939ide_outb(tf->hob_nsect, io_ports->nsect_addr);
+	if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAL)
+		tx4939ide_outb(tf->hob_lbal, io_ports->lbal_addr);
+	if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAM)
+		tx4939ide_outb(tf->hob_lbam, io_ports->lbam_addr);
+	if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAH)
+		tx4939ide_outb(tf->hob_lbah, io_ports->lbah_addr);
+
+	if (task->tf_flags & IDE_TFLAG_OUT_FEATURE)
+		tx4939ide_outb(tf->feature, io_ports->feature_addr);
+	if (task->tf_flags & IDE_TFLAG_OUT_NSECT)
+		tx4939ide_outb(tf->nsect, io_ports->nsect_addr);
+	if (task->tf_flags & IDE_TFLAG_OUT_LBAL)
+		tx4939ide_outb(tf->lbal, io_ports->lbal_addr);
+	if (task->tf_flags & IDE_TFLAG_OUT_LBAM)
+		tx4939ide_outb(tf->lbam, io_ports->lbam_addr);
+	if (task->tf_flags & IDE_TFLAG_OUT_LBAH)
+		tx4939ide_outb(tf->lbah, io_ports->lbah_addr);
+
+	if (task->tf_flags & IDE_TFLAG_OUT_DEVICE) {
+		tx4939ide_outb((tf->device & HIHI) | drive->select,
+			       io_ports->device_addr);
+		tx4939ide_tf_load_fixup(drive, task);
+	}
+}
+
+static void tx4939ide_tf_read(ide_drive_t *drive, ide_task_t *task)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	struct ide_io_ports *io_ports = &hwif->io_ports;
+	struct ide_taskfile *tf = &task->tf;
+
+	if (task->tf_flags & IDE_TFLAG_IN_DATA) {
+		u16 data;
+
+		/* no endian swap */
+		data = __raw_readw((void __iomem *)io_ports->data_addr);
+		tf->data = data & 0xff;
+		tf->hob_data = (data >> 8) & 0xff;
+	}
+
+	/* be sure we're looking at the low order bits */
+	tx4939ide_outb(ATA_DEVCTL_OBS & ~0x80, io_ports->ctl_addr);
+
+	if (task->tf_flags & IDE_TFLAG_IN_FEATURE)
+		tf->feature = tx4939ide_inb(io_ports->feature_addr);
+	if (task->tf_flags & IDE_TFLAG_IN_NSECT)
+		tf->nsect  = tx4939ide_inb(io_ports->nsect_addr);
+	if (task->tf_flags & IDE_TFLAG_IN_LBAL)
+		tf->lbal   = tx4939ide_inb(io_ports->lbal_addr);
+	if (task->tf_flags & IDE_TFLAG_IN_LBAM)
+		tf->lbam   = tx4939ide_inb(io_ports->lbam_addr);
+	if (task->tf_flags & IDE_TFLAG_IN_LBAH)
+		tf->lbah   = tx4939ide_inb(io_ports->lbah_addr);
+	if (task->tf_flags & IDE_TFLAG_IN_DEVICE)
+		tf->device = tx4939ide_inb(io_ports->device_addr);
+
+	if (task->tf_flags & IDE_TFLAG_LBA48) {
+		tx4939ide_outb(ATA_DEVCTL_OBS | 0x80, io_ports->ctl_addr);
+
+		if (task->tf_flags & IDE_TFLAG_IN_HOB_FEATURE)
+			tf->hob_feature =
+				tx4939ide_inb(io_ports->feature_addr);
+		if (task->tf_flags & IDE_TFLAG_IN_HOB_NSECT)
+			tf->hob_nsect   = tx4939ide_inb(io_ports->nsect_addr);
+		if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAL)
+			tf->hob_lbal    = tx4939ide_inb(io_ports->lbal_addr);
+		if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAM)
+			tf->hob_lbam    = tx4939ide_inb(io_ports->lbam_addr);
+		if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAH)
+			tf->hob_lbah    = tx4939ide_inb(io_ports->lbah_addr);
+	}
+}
+
+static void tx4939ide_input_data_swap(ide_drive_t *drive, struct request *rq,
+				void *buf, unsigned int len)
+{
+	unsigned long port = drive->hwif->io_ports.data_addr;
+	unsigned short *ptr = buf;
+	unsigned int count = (len + 1) / 2;
+
+	while (count--)
+		*ptr++ = cpu_to_le16(__raw_readw((void __iomem *)port));
+	__ide_flush_dcache_range((unsigned long)buf, count * 2);
+}
+
+static void tx4939ide_output_data_swap(ide_drive_t *drive, struct request *rq,
+				void *buf, unsigned int len)
+{
+	unsigned long port = drive->hwif->io_ports.data_addr;
+	unsigned short *ptr = buf;
+	unsigned int count = (len + 1) / 2;
+
+	while (count--) {
+		__raw_writew(le16_to_cpu(*ptr), (void __iomem *)port);
+		ptr++;
+	}
+	__ide_flush_dcache_range((unsigned long)buf, count * 2);
+}
+
+static const struct ide_tp_ops tx4939ide_tp_ops = {
+	.exec_command		= ide_exec_command,
+	.read_status		= ide_read_status,
+	.read_altstatus		= ide_read_altstatus,
+	.read_sff_dma_status	= tx4939ide_read_sff_dma_status,
+
+	.set_irq		= ide_set_irq,
+
+	.tf_load		= tx4939ide_tf_load,
+	.tf_read		= tx4939ide_tf_read,
+
+	.input_data		= tx4939ide_input_data_swap,
+	.output_data		= tx4939ide_output_data_swap,
+};
+
+#else	/* __LITTLE_ENDIAN */
+
+static void tx4939ide_tf_load(ide_drive_t *drive, ide_task_t *task)
+{
+	ide_tf_load(drive, task);
+	if (task->tf_flags & IDE_TFLAG_OUT_DEVICE)
+		tx4939ide_tf_load_fixup(drive, task);
+}
+
+static const struct ide_tp_ops tx4939ide_tp_ops = {
+	.exec_command		= ide_exec_command,
+	.read_status		= ide_read_status,
+	.read_altstatus		= ide_read_altstatus,
+	.read_sff_dma_status	= ide_read_sff_dma_status,
+
+	.set_irq		= ide_set_irq,
+
+	.tf_load		= tx4939ide_tf_load,
+	.tf_read		= ide_tf_read,
+
+	.input_data		= ide_input_data,
+	.output_data		= ide_output_data,
+};
+
+#endif	/* __LITTLE_ENDIAN */
+
+static const struct ide_port_ops tx4939ide_port_ops = {
+	.set_pio_mode = tx4939ide_set_pio_mode,
+	.set_dma_mode = tx4939ide_set_dma_mode,
+	.clear_irq = tx4939ide_clear_irq,
+	.cable_detect = tx4939ide_cable_detect,
+};
+
+static const struct ide_dma_ops tx4939ide_dma_ops = {
+	.dma_host_set = tx4939ide_dma_host_set,
+	.dma_setup = tx4939ide_dma_setup,
+	.dma_exec_cmd = ide_dma_exec_cmd,
+	.dma_start = ide_dma_start,
+	.dma_end = tx4939ide_dma_end,
+	.dma_test_irq = tx4939ide_dma_test_irq,
+	.dma_lost_irq = ide_dma_lost_irq,
+	.dma_timeout = ide_dma_timeout,
+};
+
+static const struct ide_port_info tx4939ide_port_info __initdata = {
+	.init_hwif = tx4939ide_init_hwif,
+	.init_dma = tx4939ide_init_dma,
+	.port_ops = &tx4939ide_port_ops,
+	.dma_ops = &tx4939ide_dma_ops,
+	.tp_ops = &tx4939ide_tp_ops,
+	.host_flags = IDE_HFLAG_MMIO,
+	.pio_mask = ATA_PIO4,
+	.mwdma_mask = ATA_MWDMA2,
+	.udma_mask = ATA_UDMA5,
+};
+
+static int __init tx4939ide_probe(struct platform_device *pdev)
+{
+	hw_regs_t hw;
+	hw_regs_t *hws[] = { &hw, NULL, NULL, NULL };
+	struct ide_host *host;
+	struct resource *res;
+	int irq, ret;
+	unsigned long mapbase;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return -ENODEV;
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	if (!devm_request_mem_region(&pdev->dev, res->start,
+				     res->end - res->start + 1, "tx4938ide"))
+		return -EBUSY;
+	mapbase = (unsigned long)devm_ioremap(&pdev->dev, res->start,
+					      res->end - res->start + 1);
+	if (!mapbase)
+		return -EBUSY;
+	memset(&hw, 0, sizeof(hw));
+	hw.io_ports.data_addr =
+		mapbase + tx4939ide_swizzlew(TX4939IDE_Data);
+	hw.io_ports.error_addr =
+		mapbase + tx4939ide_swizzleb(TX4939IDE_Error_Feature);
+	hw.io_ports.nsect_addr =
+		mapbase + tx4939ide_swizzleb(TX4939IDE_Sec);
+	hw.io_ports.lbal_addr =
+		mapbase + tx4939ide_swizzleb(TX4939IDE_LBA0);
+	hw.io_ports.lbam_addr =
+		mapbase + tx4939ide_swizzleb(TX4939IDE_LBA1);
+	hw.io_ports.lbah_addr =
+		mapbase + tx4939ide_swizzleb(TX4939IDE_LBA2);
+	hw.io_ports.device_addr =
+		mapbase + tx4939ide_swizzleb(TX4939IDE_DevHead);
+	hw.io_ports.command_addr =
+		mapbase + tx4939ide_swizzleb(TX4939IDE_Stat_Cmd);
+	hw.io_ports.ctl_addr =
+		mapbase + tx4939ide_swizzleb(TX4939IDE_AltStat_DevCtl);
+	hw.irq = irq;
+	hw.dev = &pdev->dev;
+
+	pr_info("TX4939 IDE interface (base %#lx, irq %d)\n", mapbase, irq);
+	host = ide_host_alloc(&tx4939ide_port_info, hws);
+	if (!host)
+		return -ENOMEM;
+	/* use extra_base for base address of the all registers */
+	host->ports[0]->extra_base = mapbase;
+	ret = ide_host_register(host, &tx4939ide_port_info, hws);
+	if (ret) {
+		ide_host_free(host);
+		return ret;
+	}
+	platform_set_drvdata(pdev, host);
+	return 0;
+}
+
+static int __exit tx4939ide_remove(struct platform_device *pdev)
+{
+	struct ide_host *host = platform_get_drvdata(pdev);
+
+	ide_host_remove(host);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int tx4939ide_resume(struct platform_device *dev)
+{
+	struct ide_host *host = platform_get_drvdata(dev);
+	ide_hwif_t *hwif = host->ports[0];
+
+	tx4939ide_init_hwif(hwif);
+	return 0;
+}
+#else
+#define tx4939ide_resume	NULL
+#endif
+
+static struct platform_driver tx4939ide_driver = {
+	.driver = {
+		.name = MODNAME,
+		.owner = THIS_MODULE,
+	},
+	.remove = __exit_p(tx4939ide_remove),
+	.resume = tx4939ide_resume,
+};
+
+static int __init tx4939ide_init(void)
+{
+	return platform_driver_probe(&tx4939ide_driver, tx4939ide_probe);
+}
+
+static void __exit tx4939ide_exit(void)
+{
+	platform_driver_unregister(&tx4939ide_driver);
+}
+
+module_init(tx4939ide_init);
+module_exit(tx4939ide_exit);
+
+MODULE_DESCRIPTION("TX4939 internal IDE driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:tx4939ide");
-- 
1.5.6.3

Re: [PATCH] ide: Add tx4939ide driver (v5)

[Sergei Shtylyov]

Atsushi Nemoto wrote:

> This is the driver for the Toshiba TX4939 SoC ATA controller.

> This controller has standard ATA taskfile registers and DMA
> command/status registers, but the register layout is swapped on big
> endian.  There are some other endian issue and some special registers
> which requires many custom dma_ops/tp_ops routines and build_dmatable.

> Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>

    I'm inclined to ACK the driver (besides, TX49xx patches are holding up my 
own series of patches since it needs to modify both these drivers) but I'm not 
sure about the error cleanup path now that I looked at it again -- probably' 
devres' handles all that automagically but peering into the sources didn't 
enlignten me on how it does it, so I would like to be explicitly assured. :-)
    There are also some nits, mostly ignorable...

> diff --git a/drivers/ide/mips/tx4939ide.c b/drivers/ide/mips/tx4939ide.c
> new file mode 100644
> index 0000000..9a42f83
> --- /dev/null
> +++ b/drivers/ide/mips/tx4939ide.c
> @@ -0,0 +1,756 @@
[...]
> +static void tx4939ide_set_pio_mode(ide_drive_t *drive, const u8 pio)
> +{
> +	ide_hwif_t *hwif = drive->hwif;
> +	int is_slave = drive->dn & 1;

    Here and elsewhere ANDing drive->dn with 1 seems superfluous since TX4939 
IDE controllers are single channel and therefore drive->dn should be 0 or 1...

> +static u16 tx4939ide_check_error_ints(ide_hwif_t *hwif)
> +{
> +	void __iomem *base = TX4939IDE_BASE(hwif);
> +	u16 ctl = tx4939ide_readw(base, TX4939IDE_Int_Ctl);
> +
> +	if (ctl & TX4939IDE_INT_BUSERR) {
> +		/* reset FIFO */
> +		u16 sysctl = tx4939ide_readw(base, TX4939IDE_Sys_Ctl);

    Missed a missing newline here too. :-)

> +		pr_err("%s: Error interrupt %#x (%s%s%s )\n",
> +		       hwif->name, ctl,
> +		       (ctl & TX4939IDE_INT_ADDRERR) ?
> +		       " Address-Error" : "",
> +		       (ctl & TX4939IDE_INT_DEVTIMING) ?
> +		       " DEV-Timing" : "",
> +		       (ctl & TX4939IDE_INT_BUSERR) ?

    Parens around & shouldn't be needed...

> +static u8 tx4939ide_cable_detect(ide_hwif_t *hwif)
> +{
> +	void __iomem *base = TX4939IDE_BASE(hwif);
> +
> +	return (tx4939ide_readw(base, TX4939IDE_Sys_Ctl) & 0x2000) ?

    Here as well...

> +static u8 tx4939ide_clear_dma_status(void __iomem *base)
> +{
> +	u8 dma_stat;
> +
> +	/* read DMA status for INTR & ERROR flags */
> +	dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
> +	/* clear INTR & ERROR flags */
> +	tx4939ide_writeb(dma_stat | 6, base, TX4939IDE_DMA_Stat);

    Should replace 6 with ATA_DMA_INTR | ATA_DMA_ERR to be consistent with 
other changes...

> +#ifdef __BIG_ENDIAN
> +/* custom ide_build_dmatable to handle swapped layout */
> +static int tx4939ide_build_dmatable(ide_drive_t *drive, struct request *rq)
> +{
[...]
> +		/*
> +		 * Fill in the dma table, without crossing any 64kB boundaries.

    s/dma/DMA/

> +static int tx4939ide_dma_setup(ide_drive_t *drive)
> +{
[...]
> +	/* fall back to pio! */

    s/pio/PIO/

> +	tx4939ide_writew(SECTOR_SIZE / 2, base, (drive->dn & 1) ?

    Parens around & unneeded?

> +/* returns 1 if DMA IRQ issued, 0 otherwise */
> +static int tx4939ide_dma_test_irq(ide_drive_t *drive)
> +{
> +	ide_hwif_t *hwif = drive->hwif;
> +	void __iomem *base = TX4939IDE_BASE(hwif);
> +	u16 ctl;
> +	u8 dma_stat, stat;
> +	u16 ide_int;

    Could be on the same line with 'ctl'...

> +static void tx4939ide_init_hwif(ide_hwif_t *hwif)
> +{

[...]

> +	tx4939ide_writew(0x0008, base, TX4939IDE_Lo_Burst_Cnt);
> +	tx4939ide_writew(0, base, TX4939IDE_Up_Burst_Cnt);

    I think that these fit better to tx4939ide_init_dma().

> +}
> +
> +static int tx4939ide_init_dma(ide_hwif_t *hwif, const struct ide_port_info *d)
> +{
> +	hwif->dma_base = hwif->extra_base +
> +		tx4939ide_swizzleb(TX4939IDE_DMA_Cmd);

    Doesn't it fit on the same line now?

> +	/*
> +	 * Note that we cannot use ATA_DMA_TABLE_OFS,ATA_DMA_STATUS

    No space after comma...

> +static int __init tx4939ide_probe(struct platform_device *pdev)
> +{
[...]
> +	if (!devm_request_mem_region(&pdev->dev, res->start,
> +				     res->end - res->start + 1, "tx4938ide"))
> +		return -EBUSY;
> +	mapbase = (unsigned long)devm_ioremap(&pdev->dev, res->start,
> +					      res->end - res->start + 1);
> +	if (!mapbase)
> +		return -EBUSY;

    Do you mean that on devm_ioremap() failure the memory region will be 
auto-released?

> +	host = ide_host_alloc(&tx4939ide_port_info, hws);
> +	if (!host)
> +		return -ENOMEM;
> +	/* use extra_base for base address of the all registers */
> +	host->ports[0]->extra_base = mapbase;
> +	ret = ide_host_register(host, &tx4939ide_port_info, hws);
> +	if (ret) {
> +		ide_host_free(host);
> +		return ret;
> +	}

    Same question about the error cleanup here -- will the acquired resources 
be auto-released? If so, then:

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>

MBR, Sergei

Re: [PATCH] ide: Add tx4939ide driver (v5)

[Atsushi Nemoto]

On Tue, 21 Oct 2008 20:08:41 +0400, Sergei Shtylyov <sshtylyov@ru.mvista.com> wrote:
> > This is the driver for the Toshiba TX4939 SoC ATA controller.
> 
>     I'm inclined to ACK the driver (besides, TX49xx patches are
> holding up my own series of patches since it needs to modify both
> these drivers) but I'm not sure about the error cleanup path now
> that I looked at it again -- probably' devres' handles all that
> automagically but peering into the sources didn't enlignten me on
> how it does it, so I would like to be explicitly assured. :-)

Yes, devres do it, as written in Documentation/driver-model/devres.txt.

If in doubt, 'probe_failed:' label in drivers/base/dd.c:really_probe()
is probably where you want to look at :-)

>     There are also some nits, mostly ignorable...

OK, I will send v6 patch which fixes most of them.

> > +	tx4939ide_writew(0x0008, base, TX4939IDE_Lo_Burst_Cnt);
> > +	tx4939ide_writew(0, base, TX4939IDE_Up_Burst_Cnt);
> 
>     I think that these fit better to tx4939ide_init_dma().

Unfortunately (and surprisingly) this did not work.  The kernel
crashed with strange memory corruption.  It seems Burst_Cnt must be
initialized before any transfer including PIO.  I don't know why...

>     Same question about the error cleanup here -- will the acquired resources 
> be auto-released? If so, then:
> 
> Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>

Yes.  So I will send v6 patch with your Acked-by line.  Thank you very
much!

---
Atsushi Nemoto

Re: [PATCH] ide: Add tx4939ide driver (v5)

[Bartlomiej Zolnierkiewicz]

On Tuesday 21 October 2008, Sergei Shtylyov wrote:

> > +		pr_err("%s: Error interrupt %#x (%s%s%s )\n",
> > +		       hwif->name, ctl,
> > +		       (ctl & TX4939IDE_INT_ADDRERR) ?
> > +		       " Address-Error" : "",
> > +		       (ctl & TX4939IDE_INT_DEVTIMING) ?
> > +		       " DEV-Timing" : "",
> > +		       (ctl & TX4939IDE_INT_BUSERR) ?
> 
>     Parens around & shouldn't be needed...

While the above remark is certainly correct we usually leave such parens
to ease the reading of the code and to match the other parts of the kernel...

[ No need to change it again, just a minor note... ]