ata: add Amiga Gayle PATA controller driver

Add Amiga Gayle PATA controller driver. It enables libata support
for the on-board IDE interfaces on some Amiga models (A600, A1200,
A4000 and A4000T) and also for IDE interfaces on the Zorro expansion
bus (M-Tech E-Matrix 530 expansion card).

Thanks to John Paul Adrian Glaubitz and Michael Schmitz for help
with testing the driver.

Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

3 files changed, 232 insertions, 0 deletions

diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 26b79991ba29..46f5009dcb37 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -963,6 +963,18 @@ config PATA_FALCON
 
           If unsure, say N.
 
+config PATA_GAYLE
+        tristate "Amiga Gayle PATA support"
+        depends on M68K && AMIGA
+        help
+          This option enables support for the on-board IDE
+          interfaces on some Amiga models (A600, A1200,
+          A4000 and A4000T) and also for IDE interfaces on
+          the Zorro expansion bus (M-Tech E-Matrix 530
+          expansion card).
+
+          If unsure, say N.
+
 config PATA_ISAPNP
         tristate "ISA Plug and Play PATA support"
         depends on ISAPNP
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index f1f5a3fbc777..ab08ba1276af 100644
--- a/drivers/ata/Makefile
+++ b/drivers/ata/Makefile
@@ -98,6 +98,7 @@ obj-$(CONFIG_PATA_WINBOND)	+= pata_sl82c105.o
 # SFF PIO only
 obj-$(CONFIG_PATA_CMD640_PCI)   += pata_cmd640.o
 obj-$(CONFIG_PATA_FALCON)       += pata_falcon.o
+obj-$(CONFIG_PATA_GAYLE)        += pata_gayle.o
 obj-$(CONFIG_PATA_ISAPNP)       += pata_isapnp.o
 obj-$(CONFIG_PATA_IXP4XX_CF)    += pata_ixp4xx_cf.o
 obj-$(CONFIG_PATA_MPIIX)        += pata_mpiix.o
diff --git a/drivers/ata/pata_gayle.c b/drivers/ata/pata_gayle.c
new file mode 100644
index 000000000000..65bc9f3042ce
--- /dev/null
+++ b/drivers/ata/pata_gayle.c
@@ -0,0 +1,219 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Amiga Gayle PATA controller driver
+ *
+ * Copyright (c) 2018 Samsung Electronics Co., Ltd.
+ *              http://www.samsung.com
+ *
+ * Based on gayle.c:
+ *
+ *     Created 12 Jul 1997 by Geert Uytterhoeven
+ */
+
+#include <linux/ata.h>
+#include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/libata.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/zorro.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+
+#include <asm/amigahw.h>
+#include <asm/amigaints.h>
+#include <asm/amigayle.h>
+#include <asm/ide.h>
+#include <asm/setup.h>
+
+#define DRV_NAME "pata_gayle"
+#define DRV_VERSION "0.1.0"
+
+#define GAYLE_CONTROL   0x101a
+
+static struct scsi_host_template pata_gayle_sht = {
+        ATA_PIO_SHT(DRV_NAME),
+};
+
+/* FIXME: is this needed? */
+static unsigned int pata_gayle_data_xfer(struct ata_queued_cmd *qc,
+                                         unsigned char *buf,
+                                         unsigned int buflen, int rw)
+{
+        struct ata_device *dev = qc->dev;
+        struct ata_port *ap = dev->link->ap;
+        void __iomem *data_addr = ap->ioaddr.data_addr;
+        unsigned int words = buflen >> 1;
+
+        /* Transfer multiple of 2 bytes */
+        if (rw == READ)
+                raw_insw((u16 *)data_addr, (u16 *)buf, words);
+        else
+                raw_outsw((u16 *)data_addr, (u16 *)buf, words);
+
+        /* Transfer trailing byte, if any. */
+        if (unlikely(buflen & 0x01)) {
+                unsigned char pad[2] = { };
+
+                /* Point buf to the tail of buffer */
+                buf += buflen - 1;
+
+                if (rw == READ) {
+                        raw_insw((u16 *)data_addr, (u16 *)pad, 1);
+                        *buf = pad[0];
+                } else {
+                        pad[0] = *buf;
+                        raw_outsw((u16 *)data_addr, (u16 *)pad, 1);
+                }
+                words++;
+        }
+
+        return words << 1;
+}
+
+/*
+ * Provide our own set_mode() as we don't want to change anything that has
+ * already been configured..
+ */
+static int pata_gayle_set_mode(struct ata_link *link,
+                               struct ata_device **unused)
+{
+        struct ata_device *dev;
+
+        ata_for_each_dev(dev, link, ENABLED) {
+                /* We don't really care */
+                dev->pio_mode = dev->xfer_mode = XFER_PIO_0;
+                dev->xfer_shift = ATA_SHIFT_PIO;
+                dev->flags |= ATA_DFLAG_PIO;
+                ata_dev_info(dev, "configured for PIO\n");
+        }
+        return 0;
+}
+
+static bool pata_gayle_irq_check(struct ata_port *ap)
+{
+        u8 ch;
+
+        ch = z_readb((unsigned long)ap->private_data);
+
+        return !!(ch & GAYLE_IRQ_IDE);
+}
+
+static void pata_gayle_irq_clear(struct ata_port *ap)
+{
+        (void)z_readb((unsigned long)ap->ioaddr.status_addr);
+        z_writeb(0x7c, (unsigned long)ap->private_data);
+}
+
+static struct ata_port_operations pata_gayle_a1200_ops = {
+        .inherits       = &ata_sff_port_ops,
+        .sff_data_xfer  = pata_gayle_data_xfer,
+        .sff_irq_check  = pata_gayle_irq_check,
+        .sff_irq_clear  = pata_gayle_irq_clear,
+        .cable_detect   = ata_cable_unknown,
+        .set_mode       = pata_gayle_set_mode,
+};
+
+static struct ata_port_operations pata_gayle_a4000_ops = {
+        .inherits       = &ata_sff_port_ops,
+        .sff_data_xfer  = pata_gayle_data_xfer,
+        .cable_detect   = ata_cable_unknown,
+        .set_mode       = pata_gayle_set_mode,
+};
+
+static int __init pata_gayle_init_one(struct platform_device *pdev)
+{
+        struct resource *res;
+        struct gayle_ide_platform_data *pdata;
+        struct ata_host *host;
+        struct ata_port *ap;
+        void __iomem *base;
+        int ret;
+
+        pdata = dev_get_platdata(&pdev->dev);
+
+        dev_info(&pdev->dev, "Amiga Gayle IDE controller (A%u style)\n",
+                pdata->explicit_ack ? 1200 : 4000);
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res)
+                return -ENODEV;
+
+        if (!devm_request_mem_region(&pdev->dev, res->start,
+                                     resource_size(res), DRV_NAME)) {
+                pr_err(DRV_NAME ": resources busy\n");
+                return -EBUSY;
+        }
+
+        /* allocate host */
+        host = ata_host_alloc(&pdev->dev, 1);
+        if (!host)
+                return -ENOMEM;
+
+        ap = host->ports[0];
+
+        if (pdata->explicit_ack)
+                ap->ops = &pata_gayle_a1200_ops;
+        else
+                ap->ops = &pata_gayle_a4000_ops;
+
+        ap->pio_mask = ATA_PIO4;
+        ap->flags |= ATA_FLAG_SLAVE_POSS | ATA_FLAG_NO_IORDY;
+
+        base = ZTWO_VADDR(pdata->base);
+        ap->ioaddr.data_addr            = base;
+        ap->ioaddr.error_addr           = base + 2 + 1 * 4;
+        ap->ioaddr.feature_addr         = base + 2 + 1 * 4;
+        ap->ioaddr.nsect_addr           = base + 2 + 2 * 4;
+        ap->ioaddr.lbal_addr            = base + 2 + 3 * 4;
+        ap->ioaddr.lbam_addr            = base + 2 + 4 * 4;
+        ap->ioaddr.lbah_addr            = base + 2 + 5 * 4;
+        ap->ioaddr.device_addr          = base + 2 + 6 * 4;
+        ap->ioaddr.status_addr          = base + 2 + 7 * 4;
+        ap->ioaddr.command_addr         = base + 2 + 7 * 4;
+
+        ap->ioaddr.altstatus_addr       = base + GAYLE_CONTROL;
+        ap->ioaddr.ctl_addr             = base + GAYLE_CONTROL;
+
+        ap->private_data = (void *)ZTWO_VADDR(pdata->irqport);
+
+        ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx", pdata->base,
+                      pdata->base + GAYLE_CONTROL);
+
+        ret = ata_host_activate(host, IRQ_AMIGA_PORTS, ata_sff_interrupt,
+                                IRQF_SHARED, &pata_gayle_sht);
+        if (ret)
+                return ret;
+
+        platform_set_drvdata(pdev, host);
+
+        return 0;
+}
+
+static int __exit pata_gayle_remove_one(struct platform_device *pdev)
+{
+        struct ata_host *host = platform_get_drvdata(pdev);
+
+        ata_host_detach(host);
+
+        return 0;
+}
+
+static struct platform_driver pata_gayle_driver = {
+        .remove = __exit_p(pata_gayle_remove_one),
+        .driver   = {
+                .name   = "amiga-gayle-ide",
+        },
+};
+
+module_platform_driver_probe(pata_gayle_driver, pata_gayle_init_one);
+
+MODULE_AUTHOR("Bartlomiej Zolnierkiewicz");
+MODULE_DESCRIPTION("low-level driver for Amiga Gayle PATA");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:amiga-gayle-ide");
+MODULE_VERSION(DRV_VERSION);