linux/drivers/scsi/mac_scsi.c
Uwe Kleine-König 69b43bf38b scsi: mac: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

In the error path emit an error message replacing the (less useful)
message by the core. Apart from the improved error message there is no
change in behaviour.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/89ce161dad52d99df07135531512ccecb7f25d14.1701619134.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2023-12-05 21:51:37 -05:00

548 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Generic Macintosh NCR5380 driver
*
* Copyright 1998, Michael Schmitz <mschmitz@lbl.gov>
*
* Copyright 2019 Finn Thain
*
* derived in part from:
*/
/*
* Generic Generic NCR5380 driver
*
* Copyright 1995, Russell King
*/
#include <linux/delay.h>
#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/macintosh.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 = 512;
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 */
/*
* According to "Inside Macintosh: Devices", Mac OS requires disk drivers to
* specify the number of bytes between the delays expected from a SCSI target.
* This allows the operating system to "prevent bus errors when a target fails
* to deliver the next byte within the processor bus error timeout period."
* Linux SCSI drivers lack knowledge of the timing behaviour of SCSI targets
* so bus errors are unavoidable.
*
* If a MOVE.B instruction faults, we assume that zero bytes were transferred
* and simply retry. That assumption probably depends on target behaviour but
* seems to hold up okay. The NOP provides synchronization: without it the
* fault can sometimes occur after the program counter has moved past the
* offending instruction. Post-increment addressing can't be used.
*/
#define MOVE_BYTE(operands) \
asm volatile ( \
"1: moveb " operands " \n" \
"11: nop \n" \
" addq #1,%0 \n" \
" subq #1,%1 \n" \
"40: \n" \
" \n" \
".section .fixup,\"ax\" \n" \
".even \n" \
"90: movel #1, %2 \n" \
" jra 40b \n" \
".previous \n" \
" \n" \
".section __ex_table,\"a\" \n" \
".align 4 \n" \
".long 1b,90b \n" \
".long 11b,90b \n" \
".previous \n" \
: "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
/*
* If a MOVE.W (or MOVE.L) instruction faults, it cannot be retried because
* the residual byte count would be uncertain. In that situation the MOVE_WORD
* macro clears n in the fixup section to abort the transfer.
*/
#define MOVE_WORD(operands) \
asm volatile ( \
"1: movew " operands " \n" \
"11: nop \n" \
" subq #2,%1 \n" \
"40: \n" \
" \n" \
".section .fixup,\"ax\" \n" \
".even \n" \
"90: movel #0, %1 \n" \
" movel #2, %2 \n" \
" jra 40b \n" \
".previous \n" \
" \n" \
".section __ex_table,\"a\" \n" \
".align 4 \n" \
".long 1b,90b \n" \
".long 11b,90b \n" \
".previous \n" \
: "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
#define MOVE_16_WORDS(operands) \
asm volatile ( \
"1: movew " operands " \n" \
"2: movew " operands " \n" \
"3: movew " operands " \n" \
"4: movew " operands " \n" \
"5: movew " operands " \n" \
"6: movew " operands " \n" \
"7: movew " operands " \n" \
"8: movew " operands " \n" \
"9: movew " operands " \n" \
"10: movew " operands " \n" \
"11: movew " operands " \n" \
"12: movew " operands " \n" \
"13: movew " operands " \n" \
"14: movew " operands " \n" \
"15: movew " operands " \n" \
"16: movew " operands " \n" \
"17: nop \n" \
" subl #32,%1 \n" \
"40: \n" \
" \n" \
".section .fixup,\"ax\" \n" \
".even \n" \
"90: movel #0, %1 \n" \
" movel #2, %2 \n" \
" jra 40b \n" \
".previous \n" \
" \n" \
".section __ex_table,\"a\" \n" \
".align 4 \n" \
".long 1b,90b \n" \
".long 2b,90b \n" \
".long 3b,90b \n" \
".long 4b,90b \n" \
".long 5b,90b \n" \
".long 6b,90b \n" \
".long 7b,90b \n" \
".long 8b,90b \n" \
".long 9b,90b \n" \
".long 10b,90b \n" \
".long 11b,90b \n" \
".long 12b,90b \n" \
".long 13b,90b \n" \
".long 14b,90b \n" \
".long 15b,90b \n" \
".long 16b,90b \n" \
".long 17b,90b \n" \
".previous \n" \
: "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
#define MAC_PDMA_DELAY 32
static inline int mac_pdma_recv(void __iomem *io, unsigned char *start, int n)
{
unsigned char *addr = start;
int result = 0;
if (n >= 1) {
MOVE_BYTE("%3@,%0@");
if (result)
goto out;
}
if (n >= 1 && ((unsigned long)addr & 1)) {
MOVE_BYTE("%3@,%0@");
if (result)
goto out;
}
while (n >= 32)
MOVE_16_WORDS("%3@,%0@+");
while (n >= 2)
MOVE_WORD("%3@,%0@+");
if (result)
return start - addr; /* Negated to indicate uncertain length */
if (n == 1)
MOVE_BYTE("%3@,%0@");
out:
return addr - start;
}
static inline int mac_pdma_send(unsigned char *start, void __iomem *io, int n)
{
unsigned char *addr = start;
int result = 0;
if (n >= 1) {
MOVE_BYTE("%0@,%3@");
if (result)
goto out;
}
if (n >= 1 && ((unsigned long)addr & 1)) {
MOVE_BYTE("%0@,%3@");
if (result)
goto out;
}
while (n >= 32)
MOVE_16_WORDS("%0@+,%3@");
while (n >= 2)
MOVE_WORD("%0@+,%3@");
if (result)
return start - addr; /* Negated to indicate uncertain length */
if (n == 1)
MOVE_BYTE("%0@,%3@");
out:
return addr - start;
}
/* The "SCSI DMA" chip on the IIfx implements this register. */
#define CTRL_REG 0x8
#define CTRL_INTERRUPTS_ENABLE BIT(1)
#define CTRL_HANDSHAKE_MODE BIT(3)
static inline void write_ctrl_reg(struct NCR5380_hostdata *hostdata, u32 value)
{
out_be32(hostdata->io + (CTRL_REG << 4), value);
}
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 result = 0;
hostdata->pdma_residual = len;
while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
BASR_DRQ | BASR_PHASE_MATCH,
BASR_DRQ | BASR_PHASE_MATCH, 0)) {
int bytes;
if (macintosh_config->ident == MAC_MODEL_IIFX)
write_ctrl_reg(hostdata, CTRL_HANDSHAKE_MODE |
CTRL_INTERRUPTS_ENABLE);
bytes = mac_pdma_recv(s, d, min(hostdata->pdma_residual, 512));
if (bytes > 0) {
d += bytes;
hostdata->pdma_residual -= bytes;
}
if (hostdata->pdma_residual == 0)
goto out;
if (NCR5380_poll_politely2(hostdata, STATUS_REG, SR_REQ, SR_REQ,
BUS_AND_STATUS_REG, BASR_ACK,
BASR_ACK, 0) < 0)
scmd_printk(KERN_DEBUG, hostdata->connected,
"%s: !REQ and !ACK\n", __func__);
if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
goto out;
if (bytes == 0)
udelay(MAC_PDMA_DELAY);
if (bytes >= 0)
continue;
dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
"%s: bus error (%d/%d)\n", __func__, d - dst, len);
NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
result = -1;
goto out;
}
scmd_printk(KERN_ERR, hostdata->connected,
"%s: phase mismatch or !DRQ\n", __func__);
NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
result = -1;
out:
if (macintosh_config->ident == MAC_MODEL_IIFX)
write_ctrl_reg(hostdata, CTRL_INTERRUPTS_ENABLE);
return result;
}
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 result = 0;
hostdata->pdma_residual = len;
while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
BASR_DRQ | BASR_PHASE_MATCH,
BASR_DRQ | BASR_PHASE_MATCH, 0)) {
int bytes;
if (macintosh_config->ident == MAC_MODEL_IIFX)
write_ctrl_reg(hostdata, CTRL_HANDSHAKE_MODE |
CTRL_INTERRUPTS_ENABLE);
bytes = mac_pdma_send(s, d, min(hostdata->pdma_residual, 512));
if (bytes > 0) {
s += bytes;
hostdata->pdma_residual -= bytes;
}
if (hostdata->pdma_residual == 0) {
if (NCR5380_poll_politely(hostdata, TARGET_COMMAND_REG,
TCR_LAST_BYTE_SENT,
TCR_LAST_BYTE_SENT,
0) < 0) {
scmd_printk(KERN_ERR, hostdata->connected,
"%s: Last Byte Sent timeout\n", __func__);
result = -1;
}
goto out;
}
if (NCR5380_poll_politely2(hostdata, STATUS_REG, SR_REQ, SR_REQ,
BUS_AND_STATUS_REG, BASR_ACK,
BASR_ACK, 0) < 0)
scmd_printk(KERN_DEBUG, hostdata->connected,
"%s: !REQ and !ACK\n", __func__);
if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
goto out;
if (bytes == 0)
udelay(MAC_PDMA_DELAY);
if (bytes >= 0)
continue;
dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
"%s: bus error (%d/%d)\n", __func__, s - src, len);
NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
result = -1;
goto out;
}
scmd_printk(KERN_ERR, hostdata->connected,
"%s: phase mismatch or !DRQ\n", __func__);
NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
result = -1;
out:
if (macintosh_config->ident == MAC_MODEL_IIFX)
write_ctrl_reg(hostdata, CTRL_INTERRUPTS_ENABLE);
return result;
}
static int macscsi_dma_xfer_len(struct NCR5380_hostdata *hostdata,
struct scsi_cmnd *cmd)
{
int resid = NCR5380_to_ncmd(cmd)->this_residual;
if (hostdata->flags & FLAG_NO_PSEUDO_DMA || resid < setup_use_pdma)
return 0;
return resid;
}
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,
.dma_boundary = PAGE_SIZE - 1,
.cmd_size = sizeof(struct NCR5380_cmd),
.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 void __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);
}
static struct platform_driver mac_scsi_driver = {
.remove_new = __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");