linux/drivers/scsi/sun3_scsi.c
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00

670 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Sun3 SCSI stuff by Erik Verbruggen (erik@bigmama.xtdnet.nl)
*
* Sun3 DMA routines added by Sam Creasey (sammy@sammy.net)
*
* VME support added by Sam Creasey
*
* TODO: modify this driver to support multiple Sun3 SCSI VME boards
*
* Adapted from mac_scsinew.c:
*/
/*
* 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/delay.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/platform_device.h>
#include <asm/io.h>
#include <asm/dvma.h>
#include <scsi/scsi_host.h>
/* minimum number of bytes to do dma on */
#define DMA_MIN_SIZE 129
/* Definitions for the core NCR5380 driver. */
#define NCR5380_implementation_fields /* none */
#define NCR5380_read(reg) in_8(hostdata->io + (reg))
#define NCR5380_write(reg, value) out_8(hostdata->io + (reg), value)
#define NCR5380_queue_command sun3scsi_queue_command
#define NCR5380_host_reset sun3scsi_host_reset
#define NCR5380_abort sun3scsi_abort
#define NCR5380_info sun3scsi_info
#define NCR5380_dma_xfer_len sun3scsi_dma_xfer_len
#define NCR5380_dma_recv_setup sun3scsi_dma_count
#define NCR5380_dma_send_setup sun3scsi_dma_count
#define NCR5380_dma_residual sun3scsi_dma_residual
#include "NCR5380.h"
/* dma regs start at regbase + 8, directly after the NCR regs */
struct sun3_dma_regs {
unsigned short dma_addr_hi; /* vme only */
unsigned short dma_addr_lo; /* vme only */
unsigned short dma_count_hi; /* vme only */
unsigned short dma_count_lo; /* vme only */
unsigned short udc_data; /* udc dma data reg (obio only) */
unsigned short udc_addr; /* uda dma addr reg (obio only) */
unsigned short fifo_data; /* fifo data reg,
* holds extra byte on odd dma reads
*/
unsigned short fifo_count;
unsigned short csr; /* control/status reg */
unsigned short bpack_hi; /* vme only */
unsigned short bpack_lo; /* vme only */
unsigned short ivect; /* vme only */
unsigned short fifo_count_hi; /* vme only */
};
/* ucd chip specific regs - live in dvma space */
struct sun3_udc_regs {
unsigned short rsel; /* select regs to load */
unsigned short addr_hi; /* high word of addr */
unsigned short addr_lo; /* low word */
unsigned short count; /* words to be xfer'd */
unsigned short mode_hi; /* high word of channel mode */
unsigned short mode_lo; /* low word of channel mode */
};
/* addresses of the udc registers */
#define UDC_MODE 0x38
#define UDC_CSR 0x2e /* command/status */
#define UDC_CHN_HI 0x26 /* chain high word */
#define UDC_CHN_LO 0x22 /* chain lo word */
#define UDC_CURA_HI 0x1a /* cur reg A high */
#define UDC_CURA_LO 0x0a /* cur reg A low */
#define UDC_CURB_HI 0x12 /* cur reg B high */
#define UDC_CURB_LO 0x02 /* cur reg B low */
#define UDC_MODE_HI 0x56 /* mode reg high */
#define UDC_MODE_LO 0x52 /* mode reg low */
#define UDC_COUNT 0x32 /* words to xfer */
/* some udc commands */
#define UDC_RESET 0
#define UDC_CHN_START 0xa0 /* start chain */
#define UDC_INT_ENABLE 0x32 /* channel 1 int on */
/* udc mode words */
#define UDC_MODE_HIWORD 0x40
#define UDC_MODE_LSEND 0xc2
#define UDC_MODE_LRECV 0xd2
/* udc reg selections */
#define UDC_RSEL_SEND 0x282
#define UDC_RSEL_RECV 0x182
/* bits in csr reg */
#define CSR_DMA_ACTIVE 0x8000
#define CSR_DMA_CONFLICT 0x4000
#define CSR_DMA_BUSERR 0x2000
#define CSR_FIFO_EMPTY 0x400 /* fifo flushed? */
#define CSR_SDB_INT 0x200 /* sbc interrupt pending */
#define CSR_DMA_INT 0x100 /* dma interrupt pending */
#define CSR_LEFT 0xc0
#define CSR_LEFT_3 0xc0
#define CSR_LEFT_2 0x80
#define CSR_LEFT_1 0x40
#define CSR_PACK_ENABLE 0x20
#define CSR_DMA_ENABLE 0x10
#define CSR_SEND 0x8 /* 1 = send 0 = recv */
#define CSR_FIFO 0x2 /* reset fifo */
#define CSR_INTR 0x4 /* interrupt enable */
#define CSR_SCSI 0x1
#define VME_DATA24 0x3d00
extern int sun3_map_test(unsigned long, char *);
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_hostid = -1;
module_param(setup_hostid, int, 0);
/* ms to wait after hitting dma regs */
#define SUN3_DMA_DELAY 10
/* dvma buffer to allocate -- 32k should hopefully be more than sufficient */
#define SUN3_DVMA_BUFSIZE 0xe000
static struct scsi_cmnd *sun3_dma_setup_done;
static volatile struct sun3_dma_regs *dregs;
static struct sun3_udc_regs *udc_regs;
static unsigned char *sun3_dma_orig_addr;
static unsigned long sun3_dma_orig_count;
static int sun3_dma_active;
static unsigned long last_residual;
#ifndef SUN3_SCSI_VME
/* dma controller register access functions */
static inline unsigned short sun3_udc_read(unsigned char reg)
{
unsigned short ret;
dregs->udc_addr = UDC_CSR;
udelay(SUN3_DMA_DELAY);
ret = dregs->udc_data;
udelay(SUN3_DMA_DELAY);
return ret;
}
static inline void sun3_udc_write(unsigned short val, unsigned char reg)
{
dregs->udc_addr = reg;
udelay(SUN3_DMA_DELAY);
dregs->udc_data = val;
udelay(SUN3_DMA_DELAY);
}
#endif
// safe bits for the CSR
#define CSR_GOOD 0x060f
static irqreturn_t scsi_sun3_intr(int irq, void *dev)
{
struct Scsi_Host *instance = dev;
unsigned short csr = dregs->csr;
int handled = 0;
#ifdef SUN3_SCSI_VME
dregs->csr &= ~CSR_DMA_ENABLE;
#endif
if(csr & ~CSR_GOOD) {
if (csr & CSR_DMA_BUSERR)
shost_printk(KERN_ERR, instance, "bus error in DMA\n");
if (csr & CSR_DMA_CONFLICT)
shost_printk(KERN_ERR, instance, "DMA conflict\n");
handled = 1;
}
if(csr & (CSR_SDB_INT | CSR_DMA_INT)) {
NCR5380_intr(irq, dev);
handled = 1;
}
return IRQ_RETVAL(handled);
}
/* sun3scsi_dma_setup() -- initialize the dma controller for a read/write */
static int sun3scsi_dma_setup(struct NCR5380_hostdata *hostdata,
unsigned char *data, int count, int write_flag)
{
void *addr;
if(sun3_dma_orig_addr != NULL)
dvma_unmap(sun3_dma_orig_addr);
#ifdef SUN3_SCSI_VME
addr = (void *)dvma_map_vme((unsigned long) data, count);
#else
addr = (void *)dvma_map((unsigned long) data, count);
#endif
sun3_dma_orig_addr = addr;
sun3_dma_orig_count = count;
#ifndef SUN3_SCSI_VME
dregs->fifo_count = 0;
sun3_udc_write(UDC_RESET, UDC_CSR);
/* reset fifo */
dregs->csr &= ~CSR_FIFO;
dregs->csr |= CSR_FIFO;
#endif
/* set direction */
if(write_flag)
dregs->csr |= CSR_SEND;
else
dregs->csr &= ~CSR_SEND;
#ifdef SUN3_SCSI_VME
dregs->csr |= CSR_PACK_ENABLE;
dregs->dma_addr_hi = ((unsigned long)addr >> 16);
dregs->dma_addr_lo = ((unsigned long)addr & 0xffff);
dregs->dma_count_hi = 0;
dregs->dma_count_lo = 0;
dregs->fifo_count_hi = 0;
dregs->fifo_count = 0;
#else
/* byte count for fifo */
dregs->fifo_count = count;
sun3_udc_write(UDC_RESET, UDC_CSR);
/* reset fifo */
dregs->csr &= ~CSR_FIFO;
dregs->csr |= CSR_FIFO;
if(dregs->fifo_count != count) {
shost_printk(KERN_ERR, hostdata->host,
"FIFO mismatch %04x not %04x\n",
dregs->fifo_count, (unsigned int) count);
NCR5380_dprint(NDEBUG_DMA, hostdata->host);
}
/* setup udc */
udc_regs->addr_hi = (((unsigned long)(addr) & 0xff0000) >> 8);
udc_regs->addr_lo = ((unsigned long)(addr) & 0xffff);
udc_regs->count = count/2; /* count in words */
udc_regs->mode_hi = UDC_MODE_HIWORD;
if(write_flag) {
if(count & 1)
udc_regs->count++;
udc_regs->mode_lo = UDC_MODE_LSEND;
udc_regs->rsel = UDC_RSEL_SEND;
} else {
udc_regs->mode_lo = UDC_MODE_LRECV;
udc_regs->rsel = UDC_RSEL_RECV;
}
/* announce location of regs block */
sun3_udc_write(((dvma_vtob(udc_regs) & 0xff0000) >> 8),
UDC_CHN_HI);
sun3_udc_write((dvma_vtob(udc_regs) & 0xffff), UDC_CHN_LO);
/* set dma master on */
sun3_udc_write(0xd, UDC_MODE);
/* interrupt enable */
sun3_udc_write(UDC_INT_ENABLE, UDC_CSR);
#endif
return count;
}
static int sun3scsi_dma_count(struct NCR5380_hostdata *hostdata,
unsigned char *data, int count)
{
return count;
}
static inline int sun3scsi_dma_recv_setup(struct NCR5380_hostdata *hostdata,
unsigned char *data, int count)
{
return sun3scsi_dma_setup(hostdata, data, count, 0);
}
static inline int sun3scsi_dma_send_setup(struct NCR5380_hostdata *hostdata,
unsigned char *data, int count)
{
return sun3scsi_dma_setup(hostdata, data, count, 1);
}
static int sun3scsi_dma_residual(struct NCR5380_hostdata *hostdata)
{
return last_residual;
}
static int sun3scsi_dma_xfer_len(struct NCR5380_hostdata *hostdata,
struct scsi_cmnd *cmd)
{
int wanted_len = cmd->SCp.this_residual;
if (wanted_len < DMA_MIN_SIZE || blk_rq_is_passthrough(cmd->request))
return 0;
return wanted_len;
}
static inline int sun3scsi_dma_start(unsigned long count, unsigned char *data)
{
#ifdef SUN3_SCSI_VME
unsigned short csr;
csr = dregs->csr;
dregs->dma_count_hi = (sun3_dma_orig_count >> 16);
dregs->dma_count_lo = (sun3_dma_orig_count & 0xffff);
dregs->fifo_count_hi = (sun3_dma_orig_count >> 16);
dregs->fifo_count = (sun3_dma_orig_count & 0xffff);
/* if(!(csr & CSR_DMA_ENABLE))
* dregs->csr |= CSR_DMA_ENABLE;
*/
#else
sun3_udc_write(UDC_CHN_START, UDC_CSR);
#endif
return 0;
}
/* clean up after our dma is done */
static int sun3scsi_dma_finish(int write_flag)
{
unsigned short __maybe_unused count;
unsigned short fifo;
int ret = 0;
sun3_dma_active = 0;
#ifdef SUN3_SCSI_VME
dregs->csr &= ~CSR_DMA_ENABLE;
fifo = dregs->fifo_count;
if (write_flag) {
if ((fifo > 0) && (fifo < sun3_dma_orig_count))
fifo++;
}
last_residual = fifo;
/* empty bytes from the fifo which didn't make it */
if ((!write_flag) && (dregs->csr & CSR_LEFT)) {
unsigned char *vaddr;
vaddr = (unsigned char *)dvma_vmetov(sun3_dma_orig_addr);
vaddr += (sun3_dma_orig_count - fifo);
vaddr--;
switch (dregs->csr & CSR_LEFT) {
case CSR_LEFT_3:
*vaddr = (dregs->bpack_lo & 0xff00) >> 8;
vaddr--;
fallthrough;
case CSR_LEFT_2:
*vaddr = (dregs->bpack_hi & 0x00ff);
vaddr--;
fallthrough;
case CSR_LEFT_1:
*vaddr = (dregs->bpack_hi & 0xff00) >> 8;
break;
}
}
#else
// check to empty the fifo on a read
if(!write_flag) {
int tmo = 20000; /* .2 sec */
while(1) {
if(dregs->csr & CSR_FIFO_EMPTY)
break;
if(--tmo <= 0) {
printk("sun3scsi: fifo failed to empty!\n");
return 1;
}
udelay(10);
}
}
dregs->udc_addr = 0x32;
udelay(SUN3_DMA_DELAY);
count = 2 * dregs->udc_data;
udelay(SUN3_DMA_DELAY);
fifo = dregs->fifo_count;
last_residual = fifo;
/* empty bytes from the fifo which didn't make it */
if((!write_flag) && (count - fifo) == 2) {
unsigned short data;
unsigned char *vaddr;
data = dregs->fifo_data;
vaddr = (unsigned char *)dvma_btov(sun3_dma_orig_addr);
vaddr += (sun3_dma_orig_count - fifo);
vaddr[-2] = (data & 0xff00) >> 8;
vaddr[-1] = (data & 0xff);
}
#endif
dvma_unmap(sun3_dma_orig_addr);
sun3_dma_orig_addr = NULL;
#ifdef SUN3_SCSI_VME
dregs->dma_addr_hi = 0;
dregs->dma_addr_lo = 0;
dregs->dma_count_hi = 0;
dregs->dma_count_lo = 0;
dregs->fifo_count = 0;
dregs->fifo_count_hi = 0;
dregs->csr &= ~CSR_SEND;
/* dregs->csr |= CSR_DMA_ENABLE; */
#else
sun3_udc_write(UDC_RESET, UDC_CSR);
dregs->fifo_count = 0;
dregs->csr &= ~CSR_SEND;
/* reset fifo */
dregs->csr &= ~CSR_FIFO;
dregs->csr |= CSR_FIFO;
#endif
sun3_dma_setup_done = NULL;
return ret;
}
#include "NCR5380.c"
#ifdef SUN3_SCSI_VME
#define SUN3_SCSI_NAME "Sun3 NCR5380 VME SCSI"
#define DRV_MODULE_NAME "sun3_scsi_vme"
#else
#define SUN3_SCSI_NAME "Sun3 NCR5380 SCSI"
#define DRV_MODULE_NAME "sun3_scsi"
#endif
#define PFX DRV_MODULE_NAME ": "
static struct scsi_host_template sun3_scsi_template = {
.module = THIS_MODULE,
.proc_name = DRV_MODULE_NAME,
.name = SUN3_SCSI_NAME,
.info = sun3scsi_info,
.queuecommand = sun3scsi_queue_command,
.eh_abort_handler = sun3scsi_abort,
.eh_host_reset_handler = sun3scsi_host_reset,
.can_queue = 16,
.this_id = 7,
.sg_tablesize = 1,
.cmd_per_lun = 2,
.dma_boundary = PAGE_SIZE - 1,
.cmd_size = NCR5380_CMD_SIZE,
};
static int __init sun3_scsi_probe(struct platform_device *pdev)
{
struct Scsi_Host *instance;
struct NCR5380_hostdata *hostdata;
int error;
struct resource *irq, *mem;
void __iomem *ioaddr;
int host_flags = 0;
#ifdef SUN3_SCSI_VME
int i;
#endif
if (setup_can_queue > 0)
sun3_scsi_template.can_queue = setup_can_queue;
if (setup_cmd_per_lun > 0)
sun3_scsi_template.cmd_per_lun = setup_cmd_per_lun;
if (setup_sg_tablesize > 0)
sun3_scsi_template.sg_tablesize = setup_sg_tablesize;
if (setup_hostid >= 0)
sun3_scsi_template.this_id = setup_hostid & 7;
#ifdef SUN3_SCSI_VME
ioaddr = NULL;
for (i = 0; i < 2; i++) {
unsigned char x;
irq = platform_get_resource(pdev, IORESOURCE_IRQ, i);
mem = platform_get_resource(pdev, IORESOURCE_MEM, i);
if (!irq || !mem)
break;
ioaddr = sun3_ioremap(mem->start, resource_size(mem),
SUN3_PAGE_TYPE_VME16);
dregs = (struct sun3_dma_regs *)(ioaddr + 8);
if (sun3_map_test((unsigned long)dregs, &x)) {
unsigned short oldcsr;
oldcsr = dregs->csr;
dregs->csr = 0;
udelay(SUN3_DMA_DELAY);
if (dregs->csr == 0x1400)
break;
dregs->csr = oldcsr;
}
iounmap(ioaddr);
ioaddr = NULL;
}
if (!ioaddr)
return -ENODEV;
#else
irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!irq || !mem)
return -ENODEV;
ioaddr = ioremap(mem->start, resource_size(mem));
dregs = (struct sun3_dma_regs *)(ioaddr + 8);
udc_regs = dvma_malloc(sizeof(struct sun3_udc_regs));
if (!udc_regs) {
pr_err(PFX "couldn't allocate DVMA memory!\n");
iounmap(ioaddr);
return -ENOMEM;
}
#endif
instance = scsi_host_alloc(&sun3_scsi_template,
sizeof(struct NCR5380_hostdata));
if (!instance) {
error = -ENOMEM;
goto fail_alloc;
}
instance->irq = irq->start;
hostdata = shost_priv(instance);
hostdata->base = mem->start;
hostdata->io = ioaddr;
error = NCR5380_init(instance, host_flags);
if (error)
goto fail_init;
error = request_irq(instance->irq, scsi_sun3_intr, 0,
"NCR5380", instance);
if (error) {
pr_err(PFX "scsi%d: IRQ %d not free, bailing out\n",
instance->host_no, instance->irq);
goto fail_irq;
}
dregs->csr = 0;
udelay(SUN3_DMA_DELAY);
dregs->csr = CSR_SCSI | CSR_FIFO | CSR_INTR;
udelay(SUN3_DMA_DELAY);
dregs->fifo_count = 0;
#ifdef SUN3_SCSI_VME
dregs->fifo_count_hi = 0;
dregs->dma_addr_hi = 0;
dregs->dma_addr_lo = 0;
dregs->dma_count_hi = 0;
dregs->dma_count_lo = 0;
dregs->ivect = VME_DATA24 | (instance->irq & 0xff);
#endif
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:
free_irq(instance->irq, instance);
fail_irq:
NCR5380_exit(instance);
fail_init:
scsi_host_put(instance);
fail_alloc:
if (udc_regs)
dvma_free(udc_regs);
iounmap(ioaddr);
return error;
}
static int __exit sun3_scsi_remove(struct platform_device *pdev)
{
struct Scsi_Host *instance = platform_get_drvdata(pdev);
struct NCR5380_hostdata *hostdata = shost_priv(instance);
void __iomem *ioaddr = hostdata->io;
scsi_remove_host(instance);
free_irq(instance->irq, instance);
NCR5380_exit(instance);
scsi_host_put(instance);
if (udc_regs)
dvma_free(udc_regs);
iounmap(ioaddr);
return 0;
}
static struct platform_driver sun3_scsi_driver = {
.remove = __exit_p(sun3_scsi_remove),
.driver = {
.name = DRV_MODULE_NAME,
},
};
module_platform_driver_probe(sun3_scsi_driver, sun3_scsi_probe);
MODULE_ALIAS("platform:" DRV_MODULE_NAME);
MODULE_LICENSE("GPL");