v4.19.13 snapshot.
diff --git a/drivers/scsi/mac_scsi.c b/drivers/scsi/mac_scsi.c
new file mode 100644
index 0000000..dd60573
--- /dev/null
+++ b/drivers/scsi/mac_scsi.c
@@ -0,0 +1,447 @@
+/*
+ * Generic Macintosh NCR5380 driver
+ *
+ * Copyright 1998, Michael Schmitz <mschmitz@lbl.gov>
+ *
+ * derived in part from:
+ */
+/*
+ * Generic Generic NCR5380 driver
+ *
+ * Copyright 1995, Russell King
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+
+#include <asm/hwtest.h>
+#include <asm/io.h>
+#include <asm/macints.h>
+#include <asm/setup.h>
+
+#include <scsi/scsi_host.h>
+
+/* Definitions for the core NCR5380 driver. */
+
+#define NCR5380_implementation_fields   int pdma_residual
+
+#define NCR5380_read(reg)           in_8(hostdata->io + ((reg) << 4))
+#define NCR5380_write(reg, value)   out_8(hostdata->io + ((reg) << 4), value)
+
+#define NCR5380_dma_xfer_len            macscsi_dma_xfer_len
+#define NCR5380_dma_recv_setup          macscsi_pread
+#define NCR5380_dma_send_setup          macscsi_pwrite
+#define NCR5380_dma_residual            macscsi_dma_residual
+
+#define NCR5380_intr                    macscsi_intr
+#define NCR5380_queue_command           macscsi_queue_command
+#define NCR5380_abort                   macscsi_abort
+#define NCR5380_host_reset              macscsi_host_reset
+#define NCR5380_info                    macscsi_info
+
+#include "NCR5380.h"
+
+static int setup_can_queue = -1;
+module_param(setup_can_queue, int, 0);
+static int setup_cmd_per_lun = -1;
+module_param(setup_cmd_per_lun, int, 0);
+static int setup_sg_tablesize = -1;
+module_param(setup_sg_tablesize, int, 0);
+static int setup_use_pdma = -1;
+module_param(setup_use_pdma, int, 0);
+static int setup_hostid = -1;
+module_param(setup_hostid, int, 0);
+static int setup_toshiba_delay = -1;
+module_param(setup_toshiba_delay, int, 0);
+
+#ifndef MODULE
+static int __init mac_scsi_setup(char *str)
+{
+	int ints[8];
+
+	(void)get_options(str, ARRAY_SIZE(ints), ints);
+
+	if (ints[0] < 1) {
+		pr_err("Usage: mac5380=<can_queue>[,<cmd_per_lun>[,<sg_tablesize>[,<hostid>[,<use_tags>[,<use_pdma>[,<toshiba_delay>]]]]]]\n");
+		return 0;
+	}
+	if (ints[0] >= 1)
+		setup_can_queue = ints[1];
+	if (ints[0] >= 2)
+		setup_cmd_per_lun = ints[2];
+	if (ints[0] >= 3)
+		setup_sg_tablesize = ints[3];
+	if (ints[0] >= 4)
+		setup_hostid = ints[4];
+	/* ints[5] (use_tagged_queuing) is ignored */
+	if (ints[0] >= 6)
+		setup_use_pdma = ints[6];
+	if (ints[0] >= 7)
+		setup_toshiba_delay = ints[7];
+	return 1;
+}
+
+__setup("mac5380=", mac_scsi_setup);
+#endif /* !MODULE */
+
+/* Pseudo DMA asm originally by Ove Edlund */
+
+#define CP_IO_TO_MEM(s,d,n)				\
+__asm__ __volatile__					\
+    ("    cmp.w  #4,%2\n"				\
+     "    bls    8f\n"					\
+     "    move.w %1,%%d0\n"				\
+     "    neg.b  %%d0\n"				\
+     "    and.w  #3,%%d0\n"				\
+     "    sub.w  %%d0,%2\n"				\
+     "    bra    2f\n"					\
+     " 1: move.b (%0),(%1)+\n"				\
+     " 2: dbf    %%d0,1b\n"				\
+     "    move.w %2,%%d0\n"				\
+     "    lsr.w  #5,%%d0\n"				\
+     "    bra    4f\n"					\
+     " 3: move.l (%0),(%1)+\n"				\
+     "31: move.l (%0),(%1)+\n"				\
+     "32: move.l (%0),(%1)+\n"				\
+     "33: move.l (%0),(%1)+\n"				\
+     "34: move.l (%0),(%1)+\n"				\
+     "35: move.l (%0),(%1)+\n"				\
+     "36: move.l (%0),(%1)+\n"				\
+     "37: move.l (%0),(%1)+\n"				\
+     " 4: dbf    %%d0,3b\n"				\
+     "    move.w %2,%%d0\n"				\
+     "    lsr.w  #2,%%d0\n"				\
+     "    and.w  #7,%%d0\n"				\
+     "    bra    6f\n"					\
+     " 5: move.l (%0),(%1)+\n"				\
+     " 6: dbf    %%d0,5b\n"				\
+     "    and.w  #3,%2\n"				\
+     "    bra    8f\n"					\
+     " 7: move.b (%0),(%1)+\n"				\
+     " 8: dbf    %2,7b\n"				\
+     "    moveq.l #0, %2\n"				\
+     " 9: \n"						\
+     ".section .fixup,\"ax\"\n"				\
+     "    .even\n"					\
+     "91: moveq.l #1, %2\n"				\
+     "    jra 9b\n"					\
+     "94: moveq.l #4, %2\n"				\
+     "    jra 9b\n"					\
+     ".previous\n"					\
+     ".section __ex_table,\"a\"\n"			\
+     "   .align 4\n"					\
+     "   .long  1b,91b\n"				\
+     "   .long  3b,94b\n"				\
+     "   .long 31b,94b\n"				\
+     "   .long 32b,94b\n"				\
+     "   .long 33b,94b\n"				\
+     "   .long 34b,94b\n"				\
+     "   .long 35b,94b\n"				\
+     "   .long 36b,94b\n"				\
+     "   .long 37b,94b\n"				\
+     "   .long  5b,94b\n"				\
+     "   .long  7b,91b\n"				\
+     ".previous"					\
+     : "=a"(s), "=a"(d), "=d"(n)			\
+     : "0"(s), "1"(d), "2"(n)				\
+     : "d0")
+
+static inline int macscsi_pread(struct NCR5380_hostdata *hostdata,
+                                unsigned char *dst, int len)
+{
+	u8 __iomem *s = hostdata->pdma_io + (INPUT_DATA_REG << 4);
+	unsigned char *d = dst;
+	int n = len;
+	int transferred;
+
+	while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
+	                              BASR_DRQ | BASR_PHASE_MATCH,
+	                              BASR_DRQ | BASR_PHASE_MATCH, HZ / 64)) {
+		CP_IO_TO_MEM(s, d, n);
+
+		transferred = d - dst - n;
+		hostdata->pdma_residual = len - transferred;
+
+		/* No bus error. */
+		if (n == 0)
+			return 0;
+
+		/* Target changed phase early? */
+		if (NCR5380_poll_politely2(hostdata, STATUS_REG, SR_REQ, SR_REQ,
+		                           BUS_AND_STATUS_REG, BASR_ACK, BASR_ACK, HZ / 64) < 0)
+			scmd_printk(KERN_ERR, hostdata->connected,
+			            "%s: !REQ and !ACK\n", __func__);
+		if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
+			return 0;
+
+		dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
+		         "%s: bus error (%d/%d)\n", __func__, transferred, len);
+		NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
+		d = dst + transferred;
+		n = len - transferred;
+	}
+
+	scmd_printk(KERN_ERR, hostdata->connected,
+	            "%s: phase mismatch or !DRQ\n", __func__);
+	NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
+	return -1;
+}
+
+
+#define CP_MEM_TO_IO(s,d,n)				\
+__asm__ __volatile__					\
+    ("    cmp.w  #4,%2\n"				\
+     "    bls    8f\n"					\
+     "    move.w %0,%%d0\n"				\
+     "    neg.b  %%d0\n"				\
+     "    and.w  #3,%%d0\n"				\
+     "    sub.w  %%d0,%2\n"				\
+     "    bra    2f\n"					\
+     " 1: move.b (%0)+,(%1)\n"				\
+     " 2: dbf    %%d0,1b\n"				\
+     "    move.w %2,%%d0\n"				\
+     "    lsr.w  #5,%%d0\n"				\
+     "    bra    4f\n"					\
+     " 3: move.l (%0)+,(%1)\n"				\
+     "31: move.l (%0)+,(%1)\n"				\
+     "32: move.l (%0)+,(%1)\n"				\
+     "33: move.l (%0)+,(%1)\n"				\
+     "34: move.l (%0)+,(%1)\n"				\
+     "35: move.l (%0)+,(%1)\n"				\
+     "36: move.l (%0)+,(%1)\n"				\
+     "37: move.l (%0)+,(%1)\n"				\
+     " 4: dbf    %%d0,3b\n"				\
+     "    move.w %2,%%d0\n"				\
+     "    lsr.w  #2,%%d0\n"				\
+     "    and.w  #7,%%d0\n"				\
+     "    bra    6f\n"					\
+     " 5: move.l (%0)+,(%1)\n"				\
+     " 6: dbf    %%d0,5b\n"				\
+     "    and.w  #3,%2\n"				\
+     "    bra    8f\n"					\
+     " 7: move.b (%0)+,(%1)\n"				\
+     " 8: dbf    %2,7b\n"				\
+     "    moveq.l #0, %2\n"				\
+     " 9: \n"						\
+     ".section .fixup,\"ax\"\n"				\
+     "    .even\n"					\
+     "91: moveq.l #1, %2\n"				\
+     "    jra 9b\n"					\
+     "94: moveq.l #4, %2\n"				\
+     "    jra 9b\n"					\
+     ".previous\n"					\
+     ".section __ex_table,\"a\"\n"			\
+     "   .align 4\n"					\
+     "   .long  1b,91b\n"				\
+     "   .long  3b,94b\n"				\
+     "   .long 31b,94b\n"				\
+     "   .long 32b,94b\n"				\
+     "   .long 33b,94b\n"				\
+     "   .long 34b,94b\n"				\
+     "   .long 35b,94b\n"				\
+     "   .long 36b,94b\n"				\
+     "   .long 37b,94b\n"				\
+     "   .long  5b,94b\n"				\
+     "   .long  7b,91b\n"				\
+     ".previous"					\
+     : "=a"(s), "=a"(d), "=d"(n)			\
+     : "0"(s), "1"(d), "2"(n)				\
+     : "d0")
+
+static inline int macscsi_pwrite(struct NCR5380_hostdata *hostdata,
+                                 unsigned char *src, int len)
+{
+	unsigned char *s = src;
+	u8 __iomem *d = hostdata->pdma_io + (OUTPUT_DATA_REG << 4);
+	int n = len;
+	int transferred;
+
+	while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
+	                              BASR_DRQ | BASR_PHASE_MATCH,
+	                              BASR_DRQ | BASR_PHASE_MATCH, HZ / 64)) {
+		CP_MEM_TO_IO(s, d, n);
+
+		transferred = s - src - n;
+		hostdata->pdma_residual = len - transferred;
+
+		/* Target changed phase early? */
+		if (NCR5380_poll_politely2(hostdata, STATUS_REG, SR_REQ, SR_REQ,
+		                           BUS_AND_STATUS_REG, BASR_ACK, BASR_ACK, HZ / 64) < 0)
+			scmd_printk(KERN_ERR, hostdata->connected,
+			            "%s: !REQ and !ACK\n", __func__);
+		if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
+			return 0;
+
+		/* No bus error. */
+		if (n == 0) {
+			if (NCR5380_poll_politely(hostdata, TARGET_COMMAND_REG,
+			                          TCR_LAST_BYTE_SENT,
+			                          TCR_LAST_BYTE_SENT, HZ / 64) < 0)
+				scmd_printk(KERN_ERR, hostdata->connected,
+				            "%s: Last Byte Sent timeout\n", __func__);
+			return 0;
+		}
+
+		dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
+		         "%s: bus error (%d/%d)\n", __func__, transferred, len);
+		NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
+		s = src + transferred;
+		n = len - transferred;
+	}
+
+	scmd_printk(KERN_ERR, hostdata->connected,
+	            "%s: phase mismatch or !DRQ\n", __func__);
+	NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
+
+	return -1;
+}
+
+static int macscsi_dma_xfer_len(struct NCR5380_hostdata *hostdata,
+                                struct scsi_cmnd *cmd)
+{
+	if (hostdata->flags & FLAG_NO_PSEUDO_DMA ||
+	    cmd->SCp.this_residual < 16)
+		return 0;
+
+	return cmd->SCp.this_residual;
+}
+
+static int macscsi_dma_residual(struct NCR5380_hostdata *hostdata)
+{
+	return hostdata->pdma_residual;
+}
+
+#include "NCR5380.c"
+
+#define DRV_MODULE_NAME         "mac_scsi"
+#define PFX                     DRV_MODULE_NAME ": "
+
+static struct scsi_host_template mac_scsi_template = {
+	.module			= THIS_MODULE,
+	.proc_name		= DRV_MODULE_NAME,
+	.name			= "Macintosh NCR5380 SCSI",
+	.info			= macscsi_info,
+	.queuecommand		= macscsi_queue_command,
+	.eh_abort_handler	= macscsi_abort,
+	.eh_host_reset_handler	= macscsi_host_reset,
+	.can_queue		= 16,
+	.this_id		= 7,
+	.sg_tablesize		= 1,
+	.cmd_per_lun		= 2,
+	.use_clustering		= DISABLE_CLUSTERING,
+	.cmd_size		= NCR5380_CMD_SIZE,
+	.max_sectors		= 128,
+};
+
+static int __init mac_scsi_probe(struct platform_device *pdev)
+{
+	struct Scsi_Host *instance;
+	struct NCR5380_hostdata *hostdata;
+	int error;
+	int host_flags = 0;
+	struct resource *irq, *pio_mem, *pdma_mem = NULL;
+
+	pio_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!pio_mem)
+		return -ENODEV;
+
+	pdma_mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+
+	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+
+	if (!hwreg_present((unsigned char *)pio_mem->start +
+	                   (STATUS_REG << 4))) {
+		pr_info(PFX "no device detected at %pap\n", &pio_mem->start);
+		return -ENODEV;
+	}
+
+	if (setup_can_queue > 0)
+		mac_scsi_template.can_queue = setup_can_queue;
+	if (setup_cmd_per_lun > 0)
+		mac_scsi_template.cmd_per_lun = setup_cmd_per_lun;
+	if (setup_sg_tablesize >= 0)
+		mac_scsi_template.sg_tablesize = setup_sg_tablesize;
+	if (setup_hostid >= 0)
+		mac_scsi_template.this_id = setup_hostid & 7;
+
+	instance = scsi_host_alloc(&mac_scsi_template,
+	                           sizeof(struct NCR5380_hostdata));
+	if (!instance)
+		return -ENOMEM;
+
+	if (irq)
+		instance->irq = irq->start;
+	else
+		instance->irq = NO_IRQ;
+
+	hostdata = shost_priv(instance);
+	hostdata->base = pio_mem->start;
+	hostdata->io = (u8 __iomem *)pio_mem->start;
+
+	if (pdma_mem && setup_use_pdma)
+		hostdata->pdma_io = (u8 __iomem *)pdma_mem->start;
+	else
+		host_flags |= FLAG_NO_PSEUDO_DMA;
+
+	host_flags |= setup_toshiba_delay > 0 ? FLAG_TOSHIBA_DELAY : 0;
+
+	error = NCR5380_init(instance, host_flags | FLAG_LATE_DMA_SETUP);
+	if (error)
+		goto fail_init;
+
+	if (instance->irq != NO_IRQ) {
+		error = request_irq(instance->irq, macscsi_intr, IRQF_SHARED,
+		                    "NCR5380", instance);
+		if (error)
+			goto fail_irq;
+	}
+
+	NCR5380_maybe_reset_bus(instance);
+
+	error = scsi_add_host(instance, NULL);
+	if (error)
+		goto fail_host;
+
+	platform_set_drvdata(pdev, instance);
+
+	scsi_scan_host(instance);
+	return 0;
+
+fail_host:
+	if (instance->irq != NO_IRQ)
+		free_irq(instance->irq, instance);
+fail_irq:
+	NCR5380_exit(instance);
+fail_init:
+	scsi_host_put(instance);
+	return error;
+}
+
+static int __exit mac_scsi_remove(struct platform_device *pdev)
+{
+	struct Scsi_Host *instance = platform_get_drvdata(pdev);
+
+	scsi_remove_host(instance);
+	if (instance->irq != NO_IRQ)
+		free_irq(instance->irq, instance);
+	NCR5380_exit(instance);
+	scsi_host_put(instance);
+	return 0;
+}
+
+static struct platform_driver mac_scsi_driver = {
+	.remove = __exit_p(mac_scsi_remove),
+	.driver = {
+		.name	= DRV_MODULE_NAME,
+	},
+};
+
+module_platform_driver_probe(mac_scsi_driver, mac_scsi_probe);
+
+MODULE_ALIAS("platform:" DRV_MODULE_NAME);
+MODULE_LICENSE("GPL");