pata_ixp4xx_cf.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* ixp4xx PATA/Compact Flash driver
* Copyright (C) 2006-07 Tower Technologies
* Author: Alessandro Zummo <a.zummo@towertech.it>
*
* An ATA driver to handle a Compact Flash connected
* to the ixp4xx expansion bus in TrueIDE mode. The CF
* must have it chip selects connected to two CS lines
* on the ixp4xx. In the irq is not available, you might
* want to modify both this driver and libata to run in
* polling mode.
*/
#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/regmap.h>
#include <scsi/scsi_host.h>
#define DRV_NAME "pata_ixp4xx_cf"
#define DRV_VERSION "1.0"
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)
{
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;
}
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_info(adev, "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 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 *ixpp = ap->host->private_data;
unsigned long flags;
ata_dev_dbg(adev, "%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.
*/
ixp4xx_set_16bit_timing(ixpp, adev->pio_mode);
udelay(5);
/* Transfer multiple of 2 bytes */
if (rw == READ)
for (i = 0; i < words; i++)
buf16[i] = readw(mmio);
else
for (i = 0; i < words; i++)
writew(buf16[i], mmio);
/* Transfer trailing 1 byte, if any. */
if (unlikely(buflen & 0x01)) {
u16 align_buf[1] = { 0 };
unsigned char *trailing_buf = buf + buflen - 1;
if (rw == READ) {
align_buf[0] = readw(mmio);
memcpy(trailing_buf, align_buf, 1);
} else {
memcpy(align_buf, trailing_buf, 1);
writew(align_buf[0], mmio);
}
words++;
}
ixp4xx_set_8bit_timing(ixpp, adev->pio_mode);
udelay(5);
spin_unlock_irqrestore(ap->lock, flags);
return words << 1;
}
static struct scsi_host_template ixp4xx_sht = {
ATA_PIO_SHT(DRV_NAME),
};
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_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 *ixpp,
unsigned long raw_cmd, unsigned long raw_ctl)
{
struct ata_ioports *ioaddr = &ap->ioaddr;
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);
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 *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;
cmd = platform_get_resource(pdev, IORESOURCE_MEM, 0);
ctl = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (!cmd || !ctl)
return -EINVAL;
ixpp = devm_kzalloc(dev, sizeof(*ixpp), GFP_KERNEL);
if (!ixpp)
return -ENOMEM;
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 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;
ixpp->host = ata_host_alloc_pinfo(dev, ppi, 1);
if (!ixpp->host)
return -ENOMEM;
ixpp->host->private_data = ixpp;
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);
if (irq > 0)
irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
else if (irq < 0)
return irq;
else
return -EINVAL;
/* Just one port to set up */
ixp4xx_setup_port(ixpp->host->ports[0], ixpp, cmd->start, ctl->start);
ata_print_version_once(dev, DRV_VERSION);
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", },
{ /* sentinel */ }
};
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,
};
module_platform_driver(ixp4xx_pata_platform_driver);
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("low-level driver for ixp4xx Compact Flash PATA");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);
MODULE_ALIAS("platform:" DRV_NAME);