Merge tag 'ixp4xx-drivers-arm-soc-v5.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik into arm/drivers

IXP4xx driver updates for modernizing the IXP4xx platforms,
taregeted for v5.15:

- Add DT bindings to the expansion bus and PATA libata driver.

- Add a new expansion bus driver.

- Rewrite the watchdog driver to use the watchdog core and
  spawn from the timer (clocksource) driver.

- Refactor the PATA/libata driver to probe from the device
  tree and use the expansion bus driver to manipulate chip
  select timings directly.

* tag 'ixp4xx-drivers-arm-soc-v5.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik:
  pata: ixp4xx: Rewrite to use device tree
  pata: ixp4xx: Add DT bindings
  pata: ixp4xx: Refer to cmd and ctl rather than csN
  pata: ixp4xx: Use IS_ENABLED() to determine endianness
  pata: ixp4xx: Use local dev variable
  watchdog: ixp4xx: Rewrite driver to use core
  bus: ixp4xx: Add a driver for IXP4xx expansion bus
  bus: ixp4xx: Add DT bindings for the IXP4xx expansion bus

Link: https://lore.kernel.org/r/CACRpkdZaCosXsgp02nuUbd_nEvdxm5-z0+d0oSA97UTWQ0RQQg@mail.gmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 185 insertions, 79 deletions

diff --git a/drivers/ata/pata_ixp4xx_cf.c b/drivers/ata/pata_ixp4xx_cf.c
index 5881d64af943..99c63087c8ae 100644
--- a/drivers/ata/pata_ixp4xx_cf.c
+++ b/drivers/ata/pata_ixp4xx_cf.c
@@ -13,45 +13,134 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/libata.h>
 #include <linux/irq.h>
 #include <linux/platform_device.h>
-#include <linux/platform_data/pata_ixp4xx_cf.h>
+#include <linux/regmap.h>
 #include <scsi/scsi_host.h>
 
 #define DRV_NAME	"pata_ixp4xx_cf"
-#define DRV_VERSION	"0.2"
+#define DRV_VERSION	"1.0"
 
-static int ixp4xx_set_mode(struct ata_link *link, struct ata_device **error)
+struct ixp4xx_pata {
+	struct ata_host *host;
+	struct regmap *rmap;
+	u32 cmd_csreg;
+	void __iomem *cmd;
+	void __iomem *ctl;
+};
+
+#define IXP4XX_EXP_TIMING_STRIDE	0x04
+/* The timings for the chipselect is in bits 29..16 */
+#define IXP4XX_EXP_T1_T5_MASK	GENMASK(29, 16)
+#define IXP4XX_EXP_PIO_0_8	0x0a470000
+#define IXP4XX_EXP_PIO_1_8	0x06430000
+#define IXP4XX_EXP_PIO_2_8	0x02410000
+#define IXP4XX_EXP_PIO_3_8	0x00820000
+#define IXP4XX_EXP_PIO_4_8	0x00400000
+#define IXP4XX_EXP_PIO_0_16	0x29640000
+#define IXP4XX_EXP_PIO_1_16	0x05030000
+#define IXP4XX_EXP_PIO_2_16	0x00b20000
+#define IXP4XX_EXP_PIO_3_16	0x00820000
+#define IXP4XX_EXP_PIO_4_16	0x00400000
+#define IXP4XX_EXP_BW_MASK	(BIT(6)|BIT(0))
+#define IXP4XX_EXP_BYTE_RD16	BIT(6) /* Byte reads on half-word devices */
+#define IXP4XX_EXP_BYTE_EN	BIT(0) /* Use 8bit data bus if set */
+
+static void ixp4xx_set_8bit_timing(struct ixp4xx_pata *ixpp, u8 pio_mode)
+{
+	switch (pio_mode) {
+	case XFER_PIO_0:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_0_8);
+		break;
+	case XFER_PIO_1:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_1_8);
+		break;
+	case XFER_PIO_2:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_2_8);
+		break;
+	case XFER_PIO_3:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_3_8);
+		break;
+	case XFER_PIO_4:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_4_8);
+		break;
+	default:
+		break;
+	}
+	regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+			   IXP4XX_EXP_BW_MASK, IXP4XX_EXP_BYTE_RD16|IXP4XX_EXP_BYTE_EN);
+}
+
+static void ixp4xx_set_16bit_timing(struct ixp4xx_pata *ixpp, u8 pio_mode)
 {
-	struct ata_device *dev;
-
-	ata_for_each_dev(dev, link, ENABLED) {
-		ata_dev_info(dev, "configured for PIO0\n");
-		dev->pio_mode = XFER_PIO_0;
-		dev->xfer_mode = XFER_PIO_0;
-		dev->xfer_shift = ATA_SHIFT_PIO;
-		dev->flags |= ATA_DFLAG_PIO;
+	switch (pio_mode){
+	case XFER_PIO_0:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_0_16);
+		break;
+	case XFER_PIO_1:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_1_16);
+		break;
+	case XFER_PIO_2:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_2_16);
+		break;
+	case XFER_PIO_3:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_3_16);
+		break;
+	case XFER_PIO_4:
+		regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+				   IXP4XX_EXP_T1_T5_MASK, IXP4XX_EXP_PIO_4_16);
+		break;
+	default:
+		break;
 	}
-	return 0;
+	regmap_update_bits(ixpp->rmap, ixpp->cmd_csreg,
+			   IXP4XX_EXP_BW_MASK, IXP4XX_EXP_BYTE_RD16);
+}
+
+/* This sets up the timing on the chipselect CMD accordingly */
+static void ixp4xx_set_piomode(struct ata_port *ap, struct ata_device *adev)
+{
+	struct ixp4xx_pata *ixpp = ap->host->private_data;
+
+	ata_dev_printk(adev, KERN_INFO, "configured for PIO%d 8bit\n",
+		       adev->pio_mode - XFER_PIO_0);
+	ixp4xx_set_8bit_timing(ixpp, adev->pio_mode);
 }
 
+
 static unsigned int ixp4xx_mmio_data_xfer(struct ata_queued_cmd *qc,
-				unsigned char *buf, unsigned int buflen, int rw)
+					  unsigned char *buf, unsigned int buflen, int rw)
 {
 	unsigned int i;
 	unsigned int words = buflen >> 1;
 	u16 *buf16 = (u16 *) buf;
+	struct ata_device *adev = qc->dev;
 	struct ata_port *ap = qc->dev->link->ap;
 	void __iomem *mmio = ap->ioaddr.data_addr;
-	struct ixp4xx_pata_data *data = dev_get_platdata(ap->host->dev);
+	struct ixp4xx_pata *ixpp = ap->host->private_data;
+	unsigned long flags;
+
+	ata_dev_printk(adev, KERN_DEBUG, "%s %d bytes\n", (rw == READ) ? "READ" : "WRITE",
+		       buflen);
+	spin_lock_irqsave(ap->lock, flags);
 
 	/* set the expansion bus in 16bit mode and restore
 	 * 8 bit mode after the transaction.
 	 */
-	*data->cs0_cfg &= ~(0x01);
-	udelay(100);
+	ixp4xx_set_16bit_timing(ixpp, adev->pio_mode);
+	udelay(5);
 
 	/* Transfer multiple of 2 bytes */
 	if (rw == READ)
@@ -76,8 +165,10 @@ static unsigned int ixp4xx_mmio_data_xfer(struct ata_queued_cmd *qc,
 		words++;
 	}
 
-	udelay(100);
-	*data->cs0_cfg |= 0x01;
+	ixp4xx_set_8bit_timing(ixpp, adev->pio_mode);
+	udelay(5);
+
+	spin_unlock_irqrestore(ap->lock, flags);
 
 	return words << 1;
 }
@@ -90,79 +181,98 @@ static struct ata_port_operations ixp4xx_port_ops = {
 	.inherits		= &ata_sff_port_ops,
 	.sff_data_xfer		= ixp4xx_mmio_data_xfer,
 	.cable_detect		= ata_cable_40wire,
-	.set_mode		= ixp4xx_set_mode,
+	.set_piomode		= ixp4xx_set_piomode,
+};
+
+static struct ata_port_info ixp4xx_port_info = {
+	.flags		= ATA_FLAG_NO_ATAPI,
+	.pio_mask	= ATA_PIO4,
+	.port_ops	= &ixp4xx_port_ops,
 };
 
 static void ixp4xx_setup_port(struct ata_port *ap,
-			      struct ixp4xx_pata_data *data,
-			      unsigned long raw_cs0, unsigned long raw_cs1)
+			      struct ixp4xx_pata *ixpp,
+			      unsigned long raw_cmd, unsigned long raw_ctl)
 {
 	struct ata_ioports *ioaddr = &ap->ioaddr;
-	unsigned long raw_cmd = raw_cs0;
-	unsigned long raw_ctl = raw_cs1 + 0x06;
 
-	ioaddr->cmd_addr	= data->cs0;
-	ioaddr->altstatus_addr	= data->cs1 + 0x06;
-	ioaddr->ctl_addr	= data->cs1 + 0x06;
+	raw_ctl += 0x06;
+	ioaddr->cmd_addr	= ixpp->cmd;
+	ioaddr->altstatus_addr	= ixpp->ctl + 0x06;
+	ioaddr->ctl_addr	= ixpp->ctl + 0x06;
 
 	ata_sff_std_ports(ioaddr);
 
-#ifndef __ARMEB__
-
-	/* adjust the addresses to handle the address swizzling of the
-	 * ixp4xx in little endian mode.
-	 */
-
-	*(unsigned long *)&ioaddr->data_addr		^= 0x02;
-	*(unsigned long *)&ioaddr->cmd_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->altstatus_addr	^= 0x03;
-	*(unsigned long *)&ioaddr->ctl_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->error_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->feature_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->nsect_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->lbal_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->lbam_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->lbah_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->device_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->status_addr		^= 0x03;
-	*(unsigned long *)&ioaddr->command_addr		^= 0x03;
-
-	raw_cmd ^= 0x03;
-	raw_ctl ^= 0x03;
-#endif
+	if (!IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) {
+		/* adjust the addresses to handle the address swizzling of the
+		 * ixp4xx in little endian mode.
+		 */
+
+		*(unsigned long *)&ioaddr->data_addr		^= 0x02;
+		*(unsigned long *)&ioaddr->cmd_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->altstatus_addr	^= 0x03;
+		*(unsigned long *)&ioaddr->ctl_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->error_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->feature_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->nsect_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->lbal_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->lbam_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->lbah_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->device_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->status_addr		^= 0x03;
+		*(unsigned long *)&ioaddr->command_addr		^= 0x03;
+
+		raw_cmd ^= 0x03;
+		raw_ctl ^= 0x03;
+	}
 
 	ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx", raw_cmd, raw_ctl);
 }
 
 static int ixp4xx_pata_probe(struct platform_device *pdev)
 {
-	struct resource *cs0, *cs1;
-	struct ata_host *host;
-	struct ata_port *ap;
-	struct ixp4xx_pata_data *data = dev_get_platdata(&pdev->dev);
+	struct resource *cmd, *ctl;
+	struct ata_port_info pi = ixp4xx_port_info;
+	const struct ata_port_info *ppi[] = { &pi, NULL };
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct ixp4xx_pata *ixpp;
+	u32 csindex;
 	int ret;
 	int irq;
 
-	cs0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	cs1 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	cmd = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ctl = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 
-	if (!cs0 || !cs1)
+	if (!cmd || !ctl)
 		return -EINVAL;
 
-	/* allocate host */
-	host = ata_host_alloc(&pdev->dev, 1);
-	if (!host)
+	ixpp = devm_kzalloc(dev, sizeof(*ixpp), GFP_KERNEL);
+	if (!ixpp)
 		return -ENOMEM;
 
-	/* acquire resources and fill host */
-	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
+	ixpp->rmap = syscon_node_to_regmap(np->parent);
+	if (IS_ERR(ixpp->rmap))
+		return dev_err_probe(dev, PTR_ERR(ixpp->rmap), "no regmap\n");
+	/* Inspect our address to figure out what chipselect the CMD is on */
+	ret = of_property_read_u32_index(np, "reg", 0, &csindex);
 	if (ret)
-		return ret;
+		return dev_err_probe(dev, ret, "can't inspect CMD address\n");
+	dev_info(dev, "using CS%d for PIO timing configuration\n", csindex);
+	ixpp->cmd_csreg = csindex * IXP4XX_EXP_TIMING_STRIDE;
 
-	data->cs0 = devm_ioremap(&pdev->dev, cs0->start, 0x1000);
-	data->cs1 = devm_ioremap(&pdev->dev, cs1->start, 0x1000);
+	ixpp->host = ata_host_alloc_pinfo(dev, ppi, 1);
+	if (!ixpp->host)
+		return -ENOMEM;
+	ixpp->host->private_data = ixpp;
 
-	if (!data->cs0 || !data->cs1)
+	ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
+	if (ret)
+		return ret;
+
+	ixpp->cmd = devm_ioremap_resource(dev, cmd);
+	ixpp->ctl = devm_ioremap_resource(dev, ctl);
+	if (IS_ERR(ixpp->cmd) || IS_ERR(ixpp->ctl))
 		return -ENOMEM;
 
 	irq = platform_get_irq(pdev, 0);
@@ -173,27 +283,23 @@ static int ixp4xx_pata_probe(struct platform_device *pdev)
 	else
 		return -EINVAL;
 
-	/* Setup expansion bus chip selects */
-	*data->cs0_cfg = data->cs0_bits;
-	*data->cs1_cfg = data->cs1_bits;
-
-	ap = host->ports[0];
-
-	ap->ops	= &ixp4xx_port_ops;
-	ap->pio_mask = ATA_PIO4;
-	ap->flags |= ATA_FLAG_NO_ATAPI;
+	/* Just one port to set up */
+	ixp4xx_setup_port(ixpp->host->ports[0], ixpp, cmd->start, ctl->start);
 
-	ixp4xx_setup_port(ap, data, cs0->start, cs1->start);
+	ata_print_version_once(dev, DRV_VERSION);
 
-	ata_print_version_once(&pdev->dev, DRV_VERSION);
-
-	/* activate host */
-	return ata_host_activate(host, irq, ata_sff_interrupt, 0, &ixp4xx_sht);
+	return ata_host_activate(ixpp->host, irq, ata_sff_interrupt, 0, &ixp4xx_sht);
 }
 
+static const struct of_device_id ixp4xx_pata_of_match[] = {
+	{ .compatible = "intel,ixp4xx-compact-flash", },
+	{ },
+};
+
 static struct platform_driver ixp4xx_pata_platform_driver = {
 	.driver	 = {
 		.name   = DRV_NAME,
+		.of_match_table = ixp4xx_pata_of_match,
 	},
 	.probe		= ixp4xx_pata_probe,
 	.remove		= ata_platform_remove_one,