cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

mac_scsi.c (15858B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Generic Macintosh NCR5380 driver
      4 *
      5 * Copyright 1998, Michael Schmitz <mschmitz@lbl.gov>
      6 *
      7 * Copyright 2019 Finn Thain
      8 *
      9 * derived in part from:
     10 */
     11/*
     12 * Generic Generic NCR5380 driver
     13 *
     14 * Copyright 1995, Russell King
     15 */
     16
     17#include <linux/delay.h>
     18#include <linux/types.h>
     19#include <linux/module.h>
     20#include <linux/ioport.h>
     21#include <linux/init.h>
     22#include <linux/blkdev.h>
     23#include <linux/interrupt.h>
     24#include <linux/platform_device.h>
     25
     26#include <asm/hwtest.h>
     27#include <asm/io.h>
     28#include <asm/macintosh.h>
     29#include <asm/macints.h>
     30#include <asm/setup.h>
     31
     32#include <scsi/scsi_host.h>
     33
     34/* Definitions for the core NCR5380 driver. */
     35
     36#define NCR5380_implementation_fields   int pdma_residual
     37
     38#define NCR5380_read(reg)           in_8(hostdata->io + ((reg) << 4))
     39#define NCR5380_write(reg, value)   out_8(hostdata->io + ((reg) << 4), value)
     40
     41#define NCR5380_dma_xfer_len            macscsi_dma_xfer_len
     42#define NCR5380_dma_recv_setup          macscsi_pread
     43#define NCR5380_dma_send_setup          macscsi_pwrite
     44#define NCR5380_dma_residual            macscsi_dma_residual
     45
     46#define NCR5380_intr                    macscsi_intr
     47#define NCR5380_queue_command           macscsi_queue_command
     48#define NCR5380_abort                   macscsi_abort
     49#define NCR5380_host_reset              macscsi_host_reset
     50#define NCR5380_info                    macscsi_info
     51
     52#include "NCR5380.h"
     53
     54static int setup_can_queue = -1;
     55module_param(setup_can_queue, int, 0);
     56static int setup_cmd_per_lun = -1;
     57module_param(setup_cmd_per_lun, int, 0);
     58static int setup_sg_tablesize = -1;
     59module_param(setup_sg_tablesize, int, 0);
     60static int setup_use_pdma = 512;
     61module_param(setup_use_pdma, int, 0);
     62static int setup_hostid = -1;
     63module_param(setup_hostid, int, 0);
     64static int setup_toshiba_delay = -1;
     65module_param(setup_toshiba_delay, int, 0);
     66
     67#ifndef MODULE
     68static int __init mac_scsi_setup(char *str)
     69{
     70	int ints[8];
     71
     72	(void)get_options(str, ARRAY_SIZE(ints), ints);
     73
     74	if (ints[0] < 1) {
     75		pr_err("Usage: mac5380=<can_queue>[,<cmd_per_lun>[,<sg_tablesize>[,<hostid>[,<use_tags>[,<use_pdma>[,<toshiba_delay>]]]]]]\n");
     76		return 0;
     77	}
     78	if (ints[0] >= 1)
     79		setup_can_queue = ints[1];
     80	if (ints[0] >= 2)
     81		setup_cmd_per_lun = ints[2];
     82	if (ints[0] >= 3)
     83		setup_sg_tablesize = ints[3];
     84	if (ints[0] >= 4)
     85		setup_hostid = ints[4];
     86	/* ints[5] (use_tagged_queuing) is ignored */
     87	if (ints[0] >= 6)
     88		setup_use_pdma = ints[6];
     89	if (ints[0] >= 7)
     90		setup_toshiba_delay = ints[7];
     91	return 1;
     92}
     93
     94__setup("mac5380=", mac_scsi_setup);
     95#endif /* !MODULE */
     96
     97/*
     98 * According to "Inside Macintosh: Devices", Mac OS requires disk drivers to
     99 * specify the number of bytes between the delays expected from a SCSI target.
    100 * This allows the operating system to "prevent bus errors when a target fails
    101 * to deliver the next byte within the processor bus error timeout period."
    102 * Linux SCSI drivers lack knowledge of the timing behaviour of SCSI targets
    103 * so bus errors are unavoidable.
    104 *
    105 * If a MOVE.B instruction faults, we assume that zero bytes were transferred
    106 * and simply retry. That assumption probably depends on target behaviour but
    107 * seems to hold up okay. The NOP provides synchronization: without it the
    108 * fault can sometimes occur after the program counter has moved past the
    109 * offending instruction. Post-increment addressing can't be used.
    110 */
    111
    112#define MOVE_BYTE(operands) \
    113	asm volatile ( \
    114		"1:     moveb " operands "     \n" \
    115		"11:    nop                    \n" \
    116		"       addq #1,%0             \n" \
    117		"       subq #1,%1             \n" \
    118		"40:                           \n" \
    119		"                              \n" \
    120		".section .fixup,\"ax\"        \n" \
    121		".even                         \n" \
    122		"90:    movel #1, %2           \n" \
    123		"       jra 40b                \n" \
    124		".previous                     \n" \
    125		"                              \n" \
    126		".section __ex_table,\"a\"     \n" \
    127		".align  4                     \n" \
    128		".long   1b,90b                \n" \
    129		".long  11b,90b                \n" \
    130		".previous                     \n" \
    131		: "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
    132
    133/*
    134 * If a MOVE.W (or MOVE.L) instruction faults, it cannot be retried because
    135 * the residual byte count would be uncertain. In that situation the MOVE_WORD
    136 * macro clears n in the fixup section to abort the transfer.
    137 */
    138
    139#define MOVE_WORD(operands) \
    140	asm volatile ( \
    141		"1:     movew " operands "     \n" \
    142		"11:    nop                    \n" \
    143		"       subq #2,%1             \n" \
    144		"40:                           \n" \
    145		"                              \n" \
    146		".section .fixup,\"ax\"        \n" \
    147		".even                         \n" \
    148		"90:    movel #0, %1           \n" \
    149		"       movel #2, %2           \n" \
    150		"       jra 40b                \n" \
    151		".previous                     \n" \
    152		"                              \n" \
    153		".section __ex_table,\"a\"     \n" \
    154		".align  4                     \n" \
    155		".long   1b,90b                \n" \
    156		".long  11b,90b                \n" \
    157		".previous                     \n" \
    158		: "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
    159
    160#define MOVE_16_WORDS(operands) \
    161	asm volatile ( \
    162		"1:     movew " operands "     \n" \
    163		"2:     movew " operands "     \n" \
    164		"3:     movew " operands "     \n" \
    165		"4:     movew " operands "     \n" \
    166		"5:     movew " operands "     \n" \
    167		"6:     movew " operands "     \n" \
    168		"7:     movew " operands "     \n" \
    169		"8:     movew " operands "     \n" \
    170		"9:     movew " operands "     \n" \
    171		"10:    movew " operands "     \n" \
    172		"11:    movew " operands "     \n" \
    173		"12:    movew " operands "     \n" \
    174		"13:    movew " operands "     \n" \
    175		"14:    movew " operands "     \n" \
    176		"15:    movew " operands "     \n" \
    177		"16:    movew " operands "     \n" \
    178		"17:    nop                    \n" \
    179		"       subl  #32,%1           \n" \
    180		"40:                           \n" \
    181		"                              \n" \
    182		".section .fixup,\"ax\"        \n" \
    183		".even                         \n" \
    184		"90:    movel #0, %1           \n" \
    185		"       movel #2, %2           \n" \
    186		"       jra 40b                \n" \
    187		".previous                     \n" \
    188		"                              \n" \
    189		".section __ex_table,\"a\"     \n" \
    190		".align  4                     \n" \
    191		".long   1b,90b                \n" \
    192		".long   2b,90b                \n" \
    193		".long   3b,90b                \n" \
    194		".long   4b,90b                \n" \
    195		".long   5b,90b                \n" \
    196		".long   6b,90b                \n" \
    197		".long   7b,90b                \n" \
    198		".long   8b,90b                \n" \
    199		".long   9b,90b                \n" \
    200		".long  10b,90b                \n" \
    201		".long  11b,90b                \n" \
    202		".long  12b,90b                \n" \
    203		".long  13b,90b                \n" \
    204		".long  14b,90b                \n" \
    205		".long  15b,90b                \n" \
    206		".long  16b,90b                \n" \
    207		".long  17b,90b                \n" \
    208		".previous                     \n" \
    209		: "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
    210
    211#define MAC_PDMA_DELAY		32
    212
    213static inline int mac_pdma_recv(void __iomem *io, unsigned char *start, int n)
    214{
    215	unsigned char *addr = start;
    216	int result = 0;
    217
    218	if (n >= 1) {
    219		MOVE_BYTE("%3@,%0@");
    220		if (result)
    221			goto out;
    222	}
    223	if (n >= 1 && ((unsigned long)addr & 1)) {
    224		MOVE_BYTE("%3@,%0@");
    225		if (result)
    226			goto out;
    227	}
    228	while (n >= 32)
    229		MOVE_16_WORDS("%3@,%0@+");
    230	while (n >= 2)
    231		MOVE_WORD("%3@,%0@+");
    232	if (result)
    233		return start - addr; /* Negated to indicate uncertain length */
    234	if (n == 1)
    235		MOVE_BYTE("%3@,%0@");
    236out:
    237	return addr - start;
    238}
    239
    240static inline int mac_pdma_send(unsigned char *start, void __iomem *io, int n)
    241{
    242	unsigned char *addr = start;
    243	int result = 0;
    244
    245	if (n >= 1) {
    246		MOVE_BYTE("%0@,%3@");
    247		if (result)
    248			goto out;
    249	}
    250	if (n >= 1 && ((unsigned long)addr & 1)) {
    251		MOVE_BYTE("%0@,%3@");
    252		if (result)
    253			goto out;
    254	}
    255	while (n >= 32)
    256		MOVE_16_WORDS("%0@+,%3@");
    257	while (n >= 2)
    258		MOVE_WORD("%0@+,%3@");
    259	if (result)
    260		return start - addr; /* Negated to indicate uncertain length */
    261	if (n == 1)
    262		MOVE_BYTE("%0@,%3@");
    263out:
    264	return addr - start;
    265}
    266
    267/* The "SCSI DMA" chip on the IIfx implements this register. */
    268#define CTRL_REG                0x8
    269#define CTRL_INTERRUPTS_ENABLE  BIT(1)
    270#define CTRL_HANDSHAKE_MODE     BIT(3)
    271
    272static inline void write_ctrl_reg(struct NCR5380_hostdata *hostdata, u32 value)
    273{
    274	out_be32(hostdata->io + (CTRL_REG << 4), value);
    275}
    276
    277static inline int macscsi_pread(struct NCR5380_hostdata *hostdata,
    278                                unsigned char *dst, int len)
    279{
    280	u8 __iomem *s = hostdata->pdma_io + (INPUT_DATA_REG << 4);
    281	unsigned char *d = dst;
    282	int result = 0;
    283
    284	hostdata->pdma_residual = len;
    285
    286	while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
    287	                              BASR_DRQ | BASR_PHASE_MATCH,
    288	                              BASR_DRQ | BASR_PHASE_MATCH, 0)) {
    289		int bytes;
    290
    291		if (macintosh_config->ident == MAC_MODEL_IIFX)
    292			write_ctrl_reg(hostdata, CTRL_HANDSHAKE_MODE |
    293			                         CTRL_INTERRUPTS_ENABLE);
    294
    295		bytes = mac_pdma_recv(s, d, min(hostdata->pdma_residual, 512));
    296
    297		if (bytes > 0) {
    298			d += bytes;
    299			hostdata->pdma_residual -= bytes;
    300		}
    301
    302		if (hostdata->pdma_residual == 0)
    303			goto out;
    304
    305		if (NCR5380_poll_politely2(hostdata, STATUS_REG, SR_REQ, SR_REQ,
    306		                           BUS_AND_STATUS_REG, BASR_ACK,
    307		                           BASR_ACK, 0) < 0)
    308			scmd_printk(KERN_DEBUG, hostdata->connected,
    309			            "%s: !REQ and !ACK\n", __func__);
    310		if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
    311			goto out;
    312
    313		if (bytes == 0)
    314			udelay(MAC_PDMA_DELAY);
    315
    316		if (bytes >= 0)
    317			continue;
    318
    319		dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
    320		         "%s: bus error (%d/%d)\n", __func__, d - dst, len);
    321		NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
    322		result = -1;
    323		goto out;
    324	}
    325
    326	scmd_printk(KERN_ERR, hostdata->connected,
    327	            "%s: phase mismatch or !DRQ\n", __func__);
    328	NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
    329	result = -1;
    330out:
    331	if (macintosh_config->ident == MAC_MODEL_IIFX)
    332		write_ctrl_reg(hostdata, CTRL_INTERRUPTS_ENABLE);
    333	return result;
    334}
    335
    336static inline int macscsi_pwrite(struct NCR5380_hostdata *hostdata,
    337                                 unsigned char *src, int len)
    338{
    339	unsigned char *s = src;
    340	u8 __iomem *d = hostdata->pdma_io + (OUTPUT_DATA_REG << 4);
    341	int result = 0;
    342
    343	hostdata->pdma_residual = len;
    344
    345	while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
    346	                              BASR_DRQ | BASR_PHASE_MATCH,
    347	                              BASR_DRQ | BASR_PHASE_MATCH, 0)) {
    348		int bytes;
    349
    350		if (macintosh_config->ident == MAC_MODEL_IIFX)
    351			write_ctrl_reg(hostdata, CTRL_HANDSHAKE_MODE |
    352			                         CTRL_INTERRUPTS_ENABLE);
    353
    354		bytes = mac_pdma_send(s, d, min(hostdata->pdma_residual, 512));
    355
    356		if (bytes > 0) {
    357			s += bytes;
    358			hostdata->pdma_residual -= bytes;
    359		}
    360
    361		if (hostdata->pdma_residual == 0) {
    362			if (NCR5380_poll_politely(hostdata, TARGET_COMMAND_REG,
    363			                          TCR_LAST_BYTE_SENT,
    364			                          TCR_LAST_BYTE_SENT,
    365			                          0) < 0) {
    366				scmd_printk(KERN_ERR, hostdata->connected,
    367				            "%s: Last Byte Sent timeout\n", __func__);
    368				result = -1;
    369			}
    370			goto out;
    371		}
    372
    373		if (NCR5380_poll_politely2(hostdata, STATUS_REG, SR_REQ, SR_REQ,
    374		                           BUS_AND_STATUS_REG, BASR_ACK,
    375		                           BASR_ACK, 0) < 0)
    376			scmd_printk(KERN_DEBUG, hostdata->connected,
    377			            "%s: !REQ and !ACK\n", __func__);
    378		if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
    379			goto out;
    380
    381		if (bytes == 0)
    382			udelay(MAC_PDMA_DELAY);
    383
    384		if (bytes >= 0)
    385			continue;
    386
    387		dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
    388		         "%s: bus error (%d/%d)\n", __func__, s - src, len);
    389		NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
    390		result = -1;
    391		goto out;
    392	}
    393
    394	scmd_printk(KERN_ERR, hostdata->connected,
    395	            "%s: phase mismatch or !DRQ\n", __func__);
    396	NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
    397	result = -1;
    398out:
    399	if (macintosh_config->ident == MAC_MODEL_IIFX)
    400		write_ctrl_reg(hostdata, CTRL_INTERRUPTS_ENABLE);
    401	return result;
    402}
    403
    404static int macscsi_dma_xfer_len(struct NCR5380_hostdata *hostdata,
    405                                struct scsi_cmnd *cmd)
    406{
    407	int resid = NCR5380_to_ncmd(cmd)->this_residual;
    408
    409	if (hostdata->flags & FLAG_NO_PSEUDO_DMA || resid < setup_use_pdma)
    410		return 0;
    411
    412	return resid;
    413}
    414
    415static int macscsi_dma_residual(struct NCR5380_hostdata *hostdata)
    416{
    417	return hostdata->pdma_residual;
    418}
    419
    420#include "NCR5380.c"
    421
    422#define DRV_MODULE_NAME         "mac_scsi"
    423#define PFX                     DRV_MODULE_NAME ": "
    424
    425static struct scsi_host_template mac_scsi_template = {
    426	.module			= THIS_MODULE,
    427	.proc_name		= DRV_MODULE_NAME,
    428	.name			= "Macintosh NCR5380 SCSI",
    429	.info			= macscsi_info,
    430	.queuecommand		= macscsi_queue_command,
    431	.eh_abort_handler	= macscsi_abort,
    432	.eh_host_reset_handler	= macscsi_host_reset,
    433	.can_queue		= 16,
    434	.this_id		= 7,
    435	.sg_tablesize		= 1,
    436	.cmd_per_lun		= 2,
    437	.dma_boundary		= PAGE_SIZE - 1,
    438	.cmd_size		= sizeof(struct NCR5380_cmd),
    439	.max_sectors		= 128,
    440};
    441
    442static int __init mac_scsi_probe(struct platform_device *pdev)
    443{
    444	struct Scsi_Host *instance;
    445	struct NCR5380_hostdata *hostdata;
    446	int error;
    447	int host_flags = 0;
    448	struct resource *irq, *pio_mem, *pdma_mem = NULL;
    449
    450	pio_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    451	if (!pio_mem)
    452		return -ENODEV;
    453
    454	pdma_mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
    455
    456	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
    457
    458	if (!hwreg_present((unsigned char *)pio_mem->start +
    459	                   (STATUS_REG << 4))) {
    460		pr_info(PFX "no device detected at %pap\n", &pio_mem->start);
    461		return -ENODEV;
    462	}
    463
    464	if (setup_can_queue > 0)
    465		mac_scsi_template.can_queue = setup_can_queue;
    466	if (setup_cmd_per_lun > 0)
    467		mac_scsi_template.cmd_per_lun = setup_cmd_per_lun;
    468	if (setup_sg_tablesize > 0)
    469		mac_scsi_template.sg_tablesize = setup_sg_tablesize;
    470	if (setup_hostid >= 0)
    471		mac_scsi_template.this_id = setup_hostid & 7;
    472
    473	instance = scsi_host_alloc(&mac_scsi_template,
    474	                           sizeof(struct NCR5380_hostdata));
    475	if (!instance)
    476		return -ENOMEM;
    477
    478	if (irq)
    479		instance->irq = irq->start;
    480	else
    481		instance->irq = NO_IRQ;
    482
    483	hostdata = shost_priv(instance);
    484	hostdata->base = pio_mem->start;
    485	hostdata->io = (u8 __iomem *)pio_mem->start;
    486
    487	if (pdma_mem && setup_use_pdma)
    488		hostdata->pdma_io = (u8 __iomem *)pdma_mem->start;
    489	else
    490		host_flags |= FLAG_NO_PSEUDO_DMA;
    491
    492	host_flags |= setup_toshiba_delay > 0 ? FLAG_TOSHIBA_DELAY : 0;
    493
    494	error = NCR5380_init(instance, host_flags | FLAG_LATE_DMA_SETUP);
    495	if (error)
    496		goto fail_init;
    497
    498	if (instance->irq != NO_IRQ) {
    499		error = request_irq(instance->irq, macscsi_intr, IRQF_SHARED,
    500		                    "NCR5380", instance);
    501		if (error)
    502			goto fail_irq;
    503	}
    504
    505	NCR5380_maybe_reset_bus(instance);
    506
    507	error = scsi_add_host(instance, NULL);
    508	if (error)
    509		goto fail_host;
    510
    511	platform_set_drvdata(pdev, instance);
    512
    513	scsi_scan_host(instance);
    514	return 0;
    515
    516fail_host:
    517	if (instance->irq != NO_IRQ)
    518		free_irq(instance->irq, instance);
    519fail_irq:
    520	NCR5380_exit(instance);
    521fail_init:
    522	scsi_host_put(instance);
    523	return error;
    524}
    525
    526static int __exit mac_scsi_remove(struct platform_device *pdev)
    527{
    528	struct Scsi_Host *instance = platform_get_drvdata(pdev);
    529
    530	scsi_remove_host(instance);
    531	if (instance->irq != NO_IRQ)
    532		free_irq(instance->irq, instance);
    533	NCR5380_exit(instance);
    534	scsi_host_put(instance);
    535	return 0;
    536}
    537
    538static struct platform_driver mac_scsi_driver = {
    539	.remove = __exit_p(mac_scsi_remove),
    540	.driver = {
    541		.name	= DRV_MODULE_NAME,
    542	},
    543};
    544
    545module_platform_driver_probe(mac_scsi_driver, mac_scsi_probe);
    546
    547MODULE_ALIAS("platform:" DRV_MODULE_NAME);
    548MODULE_LICENSE("GPL");