// SPDX-License-Identifier: GPL-2.0-only
/*
* SCSI low-level driver for the MESH (Macintosh Enhanced SCSI Hardware)
* bus adaptor found on Power Macintosh computers.
* We assume the MESH is connected to a DBDMA (descriptor-based DMA)
* controller.
*
* Paul Mackerras, August 1996.
* Copyright (C) 1996 Paul Mackerras.
*
* Apr. 21 2002 - BenH Rework bus reset code for new error handler
* Add delay after initial bus reset
* Add module parameters
*
* Sep. 27 2003 - BenH Move to new driver model, fix some write posting
* issues
* To do:
* - handle aborts correctly
* - retry arbitration if lost (unless higher levels do this for us)
* - power down the chip when no device is detected
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/blkdev.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
#include <linux/spinlock.h>
#include <linux/pci.h>
#include <linux/pgtable.h>
#include <asm/dbdma.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/irq.h>
#include <asm/hydra.h>
#include <asm/processor.h>
#include <asm/setup.h>
#include <asm/pmac_feature.h>
#include <asm/macio.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include "mesh.h"
#if 1
#undef KERN_DEBUG
#define KERN_DEBUG KERN_WARNING
#endif
MODULE_AUTHOR("Paul Mackerras (paulus@samba.org)");
MODULE_DESCRIPTION("PowerMac MESH SCSI driver");
MODULE_LICENSE("GPL");
static int sync_rate = CONFIG_SCSI_MESH_SYNC_RATE;
static int sync_targets = 0xff;
static int resel_targets = 0xff;
static int debug_targets = 0; /* print debug for these targets */
static int init_reset_delay = CONFIG_SCSI_MESH_RESET_DELAY_MS;
module_param(sync_rate, int, 0);
MODULE_PARM_DESC(sync_rate, "Synchronous rate (0..10, 0=async)");
module_param(sync_targets, int, 0);
MODULE_PARM_DESC(sync_targets, "Bitmask of targets allowed to set synchronous");
module_param(resel_targets, int, 0);
MODULE_PARM_DESC(resel_targets, "Bitmask of targets allowed to set disconnect");
module_param(debug_targets, int, 0644);
MODULE_PARM_DESC(debug_targets, "Bitmask of debugged targets");
module_param(init_reset_delay, int, 0);
MODULE_PARM_DESC(init_reset_delay, "Initial bus reset delay (0=no reset)");
static int mesh_sync_period = 100;
static int mesh_sync_offset = 0;
static unsigned char use_active_neg = 0; /* bit mask for SEQ_ACTIVE_NEG if used */
#define ALLOW_SYNC(tgt) ((sync_targets >> (tgt)) & 1)
#define ALLOW_RESEL(tgt) ((resel_targets >> (tgt)) & 1)
#define ALLOW_DEBUG(tgt) ((debug_targets >> (tgt)) & 1)
#define DEBUG_TARGET(cmd) ((cmd) && ALLOW_DEBUG((cmd)->device->id))
#undef MESH_DBG
#define N_DBG_LOG 50
#define N_DBG_SLOG 20
#define NUM_DBG_EVENTS 13
#undef DBG_USE_TB /* bombs on 601 */
struct dbglog {
char *fmt;
u32 tb;
u8 phase;
u8 bs0;
u8 bs1;
u8 tgt;
int d;
};
enum mesh_phase {
idle,
arbitrating,
selecting,
commanding,
dataing,
statusing,
busfreeing,
disconnecting,
reselecting,
sleeping
};
enum msg_phase {
msg_none,
msg_out,
msg_out_xxx,
msg_out_last,
msg_in,
msg_in_bad,
};
enum sdtr_phase {
do_sdtr,
sdtr_sent,
sdtr_done
};
struct mesh_target {
enum sdtr_phase sdtr_state;
int sync_params;
int data_goes_out; /* guess as to data direction */
struct scsi_cmnd *current_req;
u32 saved_ptr;
#ifdef MESH_DBG
int log_ix;
int n_log;
struct dbglog log[N_DBG_LOG];
#endif
};
struct mesh_state {
volatile struct mesh_regs __iomem *mesh;
int meshintr;
volatile struct dbdma_regs __iomem *dma;
int dmaintr;
struct Scsi_Host *host;
struct mesh_state *next;
struct scsi_cmnd *request_q;
struct scsi_cmnd *request_qtail;
enum mesh_phase phase; /* what we're currently trying to do */
enum msg_phase msgphase;
int conn_tgt; /* target we're connected to */
struct scsi_cmnd *current_req; /* req we're currently working on */
int data_ptr;
int dma_started;
int dma_count;
int stat;
int aborting;
int expect_reply;
int n_msgin;
u8 msgin[16];
int n_msgout;
int last_n_msgout;
u8 msgout[16];
struct dbdma_cmd *dma_cmds; /* space for dbdma commands, aligned */
dma_addr_t dma_cmd_bus;
void *dma_cmd_space;
int dma_cmd_size;
int clk_freq;
struct mesh_target tgts[8];
struct macio_dev *mdev;
struct pci_dev* pdev;
#ifdef MESH_DBG
int log_ix;
int n_log;
struct dbglog log[N_DBG_SLOG];
#endif
};
/*
* Driver is too messy, we need a few prototypes...
*/
static void mesh_done(struct mesh_state *ms, int start_next);
static void mesh_interrupt(struct mesh_state *ms);
static void cmd_complete(struct mesh_state *ms);
static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd);
static void halt_dma(struct mesh_state *ms);
static void phase_mismatch(struct mesh_state *ms);
/*
* Some debugging & logging routines
*/
#ifdef MESH_DBG
static inline u32 readtb(void)
{
u32 tb;
#ifdef DBG_USE_TB
/* Beware: if you enable this, it will crash on 601s. */
asm ("mftb %0" : "=r" (tb) : );
#else
tb = 0;
#endif
return tb;
}
static void dlog(struct mesh_state *ms, char *fmt, int a)
{
struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
struct dbglog *tlp, *slp;
tlp = &tp->log[tp->log_ix];
slp = &ms->log[ms->log_ix];
tlp->fmt = fmt;
tlp->tb = readtb();
tlp->phase = (ms->msgphase << 4) + ms->phase;
tlp->bs0 = ms->mesh->bus_status0;
tlp->bs1 = ms->mesh->bus_status1;
tlp->tgt = ms->conn_tgt;
tlp->d = a;
*slp = *tlp;
if (++tp->log_ix >= N_DBG_LOG)
tp->log_ix = 0;
if (tp->n_log < N_DBG_LOG)
++tp->n_log;
if (++ms->log_ix >= N_DBG_SLOG)
ms->log_ix = 0;
if (ms->n_log < N_DBG_SLOG)
++ms->n_log;
}
static void dumplog(struct mesh_state *ms, int t)
{
struct mesh_target *tp = &ms->tgts[t];
struct dbglog *lp;
int i;
if (tp->n_log == 0)
return;
i = tp->log_ix - tp->n_log;
if (i < 0)
i += N_DBG_LOG;
tp->n_log = 0;
do {
lp = &tp->log[i];
printk(KERN_DEBUG "mesh log %d: bs=%.2x%.2x ph=%.2x ",
t, lp->bs1, lp->bs0, lp->phase);
#ifdef DBG_USE_TB
printk("tb=%10u ", lp->tb);
#endif
printk(lp->fmt, lp->d);
printk("\n");
if (++i >= N_DBG_LOG)
i = 0;
} while (i != tp->log_ix);
}
static void dumpslog(struct mesh_state *ms)
{
struct dbglog *lp;
int i;
if (ms->n_log == 0)
return;
i = ms->log_ix - ms->n_log;
if (i < 0)
i += N_DBG_SLOG;
ms->n_log = 0;
do {
lp = &ms->log[i];
printk(KERN_DEBUG "mesh log: bs=%.2x%.2x ph=%.2x t%d ",
lp->bs1, lp->bs0, lp->phase, lp->tgt);
#ifdef DBG_USE_TB
printk("tb=%10u ", lp->tb);
#endif
printk(lp->fmt, lp->d);
printk("\n");
if (++i >= N_DBG_SLOG)
i = 0;
} while (i != ms->log_ix);
}
#else
static inline void dlog(struct mesh_state *ms, char *fmt, int a)
{}
static inline void dumplog(struct mesh_state *ms, int tgt)
{}
static inline void dumpslog(struct mesh_state *ms)
{}
#endif /* MESH_DBG */
#define MKWORD(a, b, c, d) (((a) << 24) + ((b) << 16) + ((c) << 8) + (d))
static void
mesh_dump_regs(struct mesh_state *ms)
{
volatile struct mesh_regs __iomem *mr = ms->mesh;
volatile struct dbdma_regs __iomem *md = ms->dma;
int t;
struct mesh_target *tp;
printk(KERN_DEBUG "mesh: state at %p, regs at %p, dma at %p\n",
ms, mr, md);
printk(KERN_DEBUG " ct=%4x seq=%2x bs=%4x fc=%2x "
"exc=%2x err=%2x im=%2x int=%2x sp=%2x\n",
(mr->count_hi << 8) + mr->count_lo, mr->sequence,
(mr->bus_status1 << 8) + mr->bus_status0, mr->fifo_count,
mr->exception, mr->error, mr->intr_mask, mr->interrupt,
mr->sync_params);
while(in_8(&mr->fifo_count))
printk(KERN_DEBUG " fifo data=%.2x\n",in_8(&mr->fifo));
printk(KERN_DEBUG " dma stat=%x cmdptr=%x\n",
in_le32(&md->status), in_le32(&md->cmdptr));
printk(KERN_DEBUG " phase=%d msgphase=%d conn_tgt=%d data_ptr=%d\n",
ms->phase, ms->msgphase, ms->conn_tgt, ms->data_ptr);
printk(KERN_DEBUG " dma_st=%d dma_ct=%d n_msgout=%d\n",
ms->dma_started, ms->dma_count, ms->n_msgout);
for (t = 0; t < 8; ++t) {
tp = &ms->tgts[t];
if (tp->current_req == NULL)
continue;
printk(KERN_DEBUG " target %d: req=%p goes_out=%d saved_ptr=%d\n",
t, tp->current_req, tp->data_goes_out, tp->saved_ptr);
}
}
/*
* Flush write buffers on the bus path to the mesh
*/
static inline void mesh_flush_io(volatile struct mesh_regs __iomem *mr)
{
(void)in_8(&mr->mesh_id);
}
/* Called with meshinterrupt disabled, initialize the chipset
* and eventually do the initial bus reset. The lock must not be
* held since we can schedule.
*/
static void mesh_init(struct mesh_state *ms)
{
volatile struct mesh_regs __iomem *mr = ms->mesh;
volatile struct dbdma_regs __iomem *md = ms->dma;
mesh_flush_io(mr);
udelay(100);
/* Reset controller */
out_le32(&md->control, (RUN|PAUSE|FLUSH|WAKE) << 16); /* stop dma */
out_8(&mr->exception, 0xff); /* clear all exception bits */
out_8(&mr->error, 0xff); /* clear all error bits */
out_8(&mr->sequence, SEQ_RESETMESH);
mesh_flush_io(mr);
udelay(10);
out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
out_8(&mr->source_id, ms->host->this_id);
out_8(&mr->sel_timeout, 25); /* 250ms */
out_8(&mr->sync_params, ASYNC_PARAMS);
if (init_reset_delay) {
printk(KERN_INFO "mesh: performing initial bus reset...\n");
/* Reset bus */
out_8(&mr->bus_status1, BS1_RST); /* assert RST */
mesh_flush_io(mr);
udelay(30); /* leave it on for >= 25us */
out_8(&mr->bus_status1, 0); /* negate RST */
mesh_flush_io(mr);
/* Wait for bus to come back */
msleep(init_reset_delay);
}
/* Reconfigure controller */
out_8(&mr->interrupt, 0xff); /* clear all interrupt bits */
out_8(&mr->sequence, SEQ_FLUSHFIFO);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->sync_params, ASYNC_PARAMS);
out_8(&mr->sequence, SEQ_ENBRESEL);
ms->phase = idle;
ms->msgphase = msg_none;
}
static void mesh_start_cmd(struct mesh_state *ms, struct scsi_cmnd *cmd)
{
volatile struct mesh_regs __iomem *mr = ms->mesh;
int t, id;
id = cmd->device->id;
ms->current_req = cmd;
ms->tgts[id].data_goes_out = cmd->sc_data_direction == DMA_TO_DEVICE;
ms->tgts[id].current_req = cmd;
#if 1
if (DEBUG_TARGET(cmd)) {
int i;
printk(KERN_DEBUG "mesh_start: %p tgt=%d cmd=", cmd, id);
for (i = 0; i < cmd->cmd_len; ++i)
printk(" %x", cmd->cmnd[i]);
printk(" use_sg=%d buffer=%p bufflen=%u\n",
scsi_sg_count(cmd), scsi_sglist(cmd), scsi_bufflen(cmd));
}
#endif
if (ms->dma_started)
panic("mesh: double DMA start !\n");
ms->phase = arbitrating;
ms->msgphase = msg_none;
ms->data_ptr = 0;
ms->dma_started = 0;
ms->n_msgout = 0;
ms->last_n_msgout = 0;
ms->expect_reply = 0;
ms->conn_tgt = id;
ms->tgts[id].saved_ptr = 0;
ms->stat = DID_OK;
ms->aborting = 0;
#ifdef MESH_DBG
ms->tgts[id].n_log = 0;
dlog(ms, "start cmd=%x", (int) cmd);
#endif
/* Off we go */
dlog(ms, "about to arb, intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
out_8(&mr->interrupt, INT_CMDDONE);
out_8(&mr->sequence, SEQ_ENBRESEL);
mesh_flush_io(mr);
udelay(1);
if (in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) {
/*
* Some other device has the bus or is arbitrating for it -
* probably a target which is about to reselect us.
*/
dlog(ms, "busy b4 arb, intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception,
mr->error, mr->fifo_count));
for (t = 100; t > 0; --t) {
if ((in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) == 0)
break;
if (in_8(&mr->interrupt) != 0) {
dlog(ms, "intr b4 arb, intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception,
mr->error, mr->fifo_count));
mesh_interrupt(ms);
if (ms->phase != arbitrating)
return;
}
udelay(1);
}
if (in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) {
/* XXX should try again in a little while */
ms->stat = DID_BUS_BUSY;
ms->phase = idle;
mesh_done(ms, 0);
return;
}
}
/*
* Apparently the mesh has a bug where it will assert both its
* own bit and the target's bit on the bus during arbitration.
*/
out_8(&mr->dest_id, mr->source_id);
/*
* There appears to be a race with reselection sometimes,
* where a target reselects us just as we issue the
* arbitrate command. It seems that then the arbitrate
* command just hangs waiting for the bus to be free
* without giving us a reselection exception.
* The only way I have found to get it to respond correctly
* is this: disable reselection before issuing the arbitrate
* command, then after issuing it, if it looks like a target
* is trying to reselect us, reset the mesh and then enable
* reselection.
*/
out_8(&mr->sequence, SEQ_DISRESEL);
if (in_8(&mr->interrupt) != 0) {
dlog(ms, "intr after disresel, intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception,
mr->error, mr->fifo_count));
mesh_interrupt(ms);
if (ms->phase != arbitrating)
return;
dlog(ms, "after intr after disresel, intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception,
mr->error, mr->fifo_count));
}
out_8(&mr->sequence, SEQ_ARBITRATE);
for (t = 230; t > 0; --t) {
if (in_8(&mr->interrupt) != 0)
break;
udelay(1);
}
dlog(ms, "after arb, intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
if (in_8(&mr->interrupt) == 0 && (in_8(&mr->bus_status1) & BS1_SEL)
&& (in_8(&mr->bus_status0) & BS0_IO)) {
/* looks like a reselection - try resetting the mesh */
dlog(ms, "resel? after arb, intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
out_8(&mr->sequence, SEQ_RESETMESH);
mesh_flush_io(mr);
udelay(10);
out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
out_8(&mr->sequence, SEQ_ENBRESEL);
mesh_flush_io(mr);
for (t = 10; t > 0 && in_8(&mr->interrupt) == 0; --t)
udelay(1);
dlog(ms, "tried reset after arb, intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
#ifndef MESH_MULTIPLE_HOSTS
if (in_8(&mr->interrupt) == 0 && (in_8(&mr->bus_status1) & BS1_SEL)
&& (in_8(&mr->bus_status0) & BS0_IO)) {
printk(KERN_ERR "mesh: controller not responding"
" to reselection!\n");
/*
* If this is a target reselecting us, and the
* mesh isn't responding, the higher levels of
* the scsi code will eventually time out and
* reset the bus.
*/
}
#endif
}
}
/*
* Start the next command for a MESH.
* Should be called with interrupts disabled.
*/
static void mesh_start(struct mesh_state *ms)
{
struct scsi_cmnd *cmd, *prev, *next;
if (ms->phase != idle || ms->current_req != NULL) {
printk(KERN_ERR "inappropriate mesh_start (phase=%d, ms=%p)",
ms->phase, ms);
return;
}
while (ms->phase == idle) {
prev = NULL;
for (cmd = ms->request_q; ; cmd = (struct scsi_cmnd *) cmd->host_scribble) {
if (cmd == NULL)
return;
if (ms->tgts[cmd->device->id].current_req == NULL)
break;
prev = cmd;
}
next = (struct scsi_cmnd *) cmd->host_scribble;
if (prev == NULL)
ms->request_q = next;
else
prev->host_scribble = (void *) next;
if (next == NULL)
ms->request_qtail = prev;
mesh_start_cmd(ms, cmd);
}
}
static void mesh_done(struct mesh_state *ms, int start_next)
{
struct scsi_cmnd *cmd;
struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
cmd = ms->current_req;
ms->current_req = NULL;
tp->current_req = NULL;
if (cmd) {
struct mesh_cmd_priv *mcmd = mesh_priv(cmd);
set_host_byte(cmd, ms->stat);
set_status_byte(cmd, mcmd->status);
if (ms->stat == DID_OK)
scsi_msg_to_host_byte(cmd, mcmd->message);
if (DEBUG_TARGET(cmd)) {
printk(KERN_DEBUG "mesh_done: result = %x, data_ptr=%d, buflen=%d\n",
cmd->result, ms->data_ptr, scsi_bufflen(cmd));
#if 0
/* needs to use sg? */
if ((cmd->cmnd[0] == 0 || cmd->cmnd[0] == 0x12 || cmd->cmnd[0] == 3)
&& cmd->request_buffer != 0) {
unsigned char *b = cmd->request_buffer;
printk(KERN_DEBUG "buffer = %x %x %x %x %x %x %x %x\n",
b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7]);
}
#endif
}
mcmd->this_residual -= ms->data_ptr;
scsi_done(cmd);
}
if (start_next) {
out_8(&ms->mesh->sequence, SEQ_ENBRESEL);
mesh_flush_io(ms->mesh);
udelay(1);
ms->phase = idle;
mesh_start(ms);
}
}
static inline void add_sdtr_msg(struct mesh_state *ms)
{
int i = ms->n_msgout;
ms->msgout[i] = EXTENDED_MESSAGE;
ms->msgout[i+1] = 3;
ms->msgout[i+2] = EXTENDED_SDTR;
ms->msgout[i+3] = mesh_sync_period/4;
ms->msgout[i+4] = (ALLOW_SYNC(ms->conn_tgt)? mesh_sync_offset: 0);
ms->n_msgout = i + 5;
}
static void set_sdtr(struct mesh_state *ms, int period, int offset)
{
struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
volatile struct mesh_regs __iomem *mr = ms->mesh;
int v, tr;
tp->sdtr_state = sdtr_done;
if (offset == 0) {
/* asynchronous */
if (SYNC_OFF(tp->sync_params))
printk(KERN_INFO "mesh: target %d now asynchronous\n",
ms->conn_tgt);
tp->sync_params = ASYNC_PARAMS;
out_8(&mr->sync_params, ASYNC_PARAMS);
return;
}
/*
* We need to compute ceil(clk_freq * period / 500e6) - 2
* without incurring overflow.
*/
v = (ms->clk_freq / 5000) * period;
if (v <= 250000) {
/* special case: sync_period == 5 * clk_period */
v = 0;
/* units of tr are 100kB/s */
tr = (ms->clk_freq + 250000) / 500000;
} else {
/* sync_period == (v + 2) * 2 * clk_period */
v = (v + 99999) / 100000 - 2;
if (v > 15)
v = 15; /* oops */
tr = ((ms->clk_freq / (v + 2)) + 199999) / 200000;
}
if (offset > 15)
offset = 15; /* can't happen */
tp->sync_params = SYNC_PARAMS(offset, v);
out_8(&mr->sync_params, tp->sync_params);
printk(KERN_INFO "mesh: target %d synchronous at %d.%d MB/s\n",
ms->conn_tgt, tr/10, tr%10);
}
static void start_phase(struct mesh_state *ms)
{
int i, seq, nb;
volatile struct mesh_regs __iomem *mr = ms->mesh;
volatile struct dbdma_regs __iomem *md = ms->dma;
struct scsi_cmnd *cmd = ms->current_req;
struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
dlog(ms, "start_phase nmo/exc/fc/seq = %.8x",
MKWORD(ms->n_msgout, mr->exception, mr->fifo_count, mr->sequence));
out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
seq = use_active_neg + (ms->n_msgout? SEQ_ATN: 0);
switch (ms->msgphase) {
case msg_none:
break;
case msg_in:
out_8(&mr->count_hi, 0);
out_8(&mr->count_lo, 1);
out_8(&mr->sequence, SEQ_MSGIN + seq);
ms->n_msgin = 0;
return;
case msg_out:
/*
* To make sure ATN drops before we assert ACK for
* the last byte of the message, we have to do the
* last byte specially.
*/
if (ms->n_msgout <= 0) {
printk(KERN_ERR "mesh: msg_out but n_msgout=%d\n",
ms->n_msgout);
mesh_dump_regs(ms);
ms->msgphase = msg_none;
break;
}
if (ALLOW_DEBUG(ms->conn_tgt)) {
printk(KERN_DEBUG "mesh: sending %d msg bytes:",
ms->n_msgout);
for (i = 0; i < ms->n_msgout; ++i)
printk(" %x", ms->msgout[i]);
printk("\n");
}
dlog(ms, "msgout msg=%.8x", MKWORD(ms->n_msgout, ms->msgout[0],
ms->msgout[1], ms->msgout[2]));
out_8(&mr->count_hi, 0);
out_8(&mr->sequence, SEQ_FLUSHFIFO);
mesh_flush_io(mr);
udelay(1);
/*
* If ATN is not already asserted, we assert it, then
* issue a SEQ_MSGOUT to get the mesh to drop ACK.
*/
if ((in_8(&mr->bus_status0) & BS0_ATN) == 0) {
dlog(ms, "bus0 was %.2x explicitly asserting ATN", mr->bus_status0);
out_8(&mr->bus_status0, BS0_ATN); /* explicit ATN */
mesh_flush_io(mr);
udelay(1);
out_8(&mr->count_lo, 1);
out_8(&mr->sequence, SEQ_MSGOUT + seq);
out_8(&mr->bus_status0, 0); /* release explicit ATN */
dlog(ms,"hace: after explicit ATN bus0=%.2x",mr->bus_status0);
}
if (ms->n_msgout == 1) {
/*
* We can't issue the SEQ_MSGOUT without ATN
* until the target has asserted REQ. The logic
* in cmd_complete handles both situations:
* REQ already asserted or not.
*/
cmd_complete(ms);
} else {
out_8(&mr->count_lo, ms->n_msgout - 1);
out_8(&mr->sequence, SEQ_MSGOUT + seq);
for (i = 0; i < ms->n_msgout - 1; ++i)
out_8(&mr->fifo, ms->msgout[i]);
}
return;
default:
printk(KERN_ERR "mesh bug: start_phase msgphase=%d\n",
ms->msgphase);
}
switch (ms->phase) {
case selecting:
out_8(&mr->dest_id, ms->conn_tgt);
out_8(&mr->sequence, SEQ_SELECT + SEQ_ATN);
break;
case commanding:
out_8(&mr->sync_params, tp->sync_params);
out_8(&mr->count_hi, 0);
if (cmd) {
out_8(&mr->count_lo, cmd->cmd_len);
out_8(&mr->sequence, SEQ_COMMAND + seq);
for (i = 0; i < cmd->cmd_len; ++i)
out_8(&mr->fifo, cmd->cmnd[i]);
} else {
out_8(&mr->count_lo, 6);
out_8(&mr->sequence, SEQ_COMMAND + seq);
for (i = 0; i < 6; ++i)
out_8(&mr->fifo, 0);
}
break;
case dataing:
/* transfer data, if any */
if (!ms->dma_started) {
set_dma_cmds(ms, cmd);
out_le32(&md->cmdptr, virt_to_phys(ms->dma_cmds));
out_le32(&md->control, (RUN << 16) | RUN);
ms->dma_started = 1;
}
nb = ms->dma_count;
if (nb > 0xfff0)
nb = 0xfff0;
ms->dma_count -= nb;
ms->data_ptr += nb;
out_8(&mr->count_lo, nb);
out_8(&mr->count_hi, nb >> 8);
out_8(&mr->sequence, (tp->data_goes_out?
SEQ_DATAOUT: SEQ_DATAIN) + SEQ_DMA_MODE + seq);
break;
case statusing:
out_8(&mr->count_hi, 0);
out_8(&mr->count_lo, 1);
out_8(&mr->sequence, SEQ_STATUS + seq);
break;
case busfreeing:
case disconnecting:
out_8(&mr->sequence, SEQ_ENBRESEL);
mesh_flush_io(mr);
udelay(1);
dlog(ms, "enbresel intr/exc/err/fc=%.8x",
MKWORD(mr->interrupt, mr->exception, mr->error,
mr->fifo_count));
out_8(&mr->sequence, SEQ_BUSFREE);
break;
default:
printk(KERN_ERR "mesh: start_phase called with phase=%d\n",
ms->phase);
dumpslog(ms);
}
}
static inline void get_msgin(struct mesh_state *ms)
{
volatile struct mesh_regs __iomem *mr = ms->mesh;
int i, n;
n = mr->fifo_count;
if (n != 0) {
i = ms->n_msgin;
ms->n_msgin = i + n;
for (; n > 0; --n)
ms->msgin[i++] = in_8(&mr->fifo);
}
}
static inline int msgin_length(struct mesh_state *ms)
{
int b, n;
n = 1;
if (ms->n_msgin > 0) {
b = ms->msgin[0];
if (b == 1) {
/* extended message */
n = ms->n_msgin < 2? 2: ms->msgin[1] + 2;
} else if (0x20 <= b && b <= 0x2f) {
/* 2-byte message */
n = 2;
}
}
return n;
}
static void reselected(struct mesh_state *ms)
{
volatile struct mesh_regs __iomem *mr = ms->mesh;
struct scsi_cmnd *cmd;
struct mesh_target *tp;
int b, t, prev;
switch (ms->phase) {
case idle:
break;
case arbitrating:
if ((cmd = ms->current_req) != NULL) {
/* put the command back on the queue */
cmd->host_scribble = (void *) ms->request_q;
if (ms->request_q == NULL)
ms->request_qtail = cmd;
ms->request_q = cmd;
tp = &ms->tgts[cmd->device->id];
tp->current_req = NULL;
}
break;
case busfreeing:
ms->phase = reselecting;
mesh_done(ms, 0);
break;
case disconnecting:
break;
default:
printk(KERN_ERR "mesh: reselected in phase %d/%d tgt %d\n",
ms->msgphase, ms->phase, ms->conn_tgt);
dumplog(ms, ms->conn_tgt);
dumpslog(ms);
}
if (ms->dma_started) {
printk(KERN_ERR "mesh: reselected with DMA started !\n");
halt_dma(ms);
}
ms->current_req = NULL;
ms->phase = dataing;
ms->msgphase = msg_in;
ms->n_msgout = 0;
ms->last_n_msgout = 0;
prev = ms->conn_tgt;
/*
* We seem to get abortive reselections sometimes.
*/
while ((in_8(&mr->bus_status1) & BS1_BSY) == 0) {
static int mesh_aborted_resels;
mesh_aborted_resels++;
out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->sequence, SEQ_ENBRESEL);
mesh_flush_io(mr);
udelay(5);
dlog(ms, "extra resel err/exc/fc = %.6x",
MKWORD(0, mr->error, mr->exception, mr->fifo_count));
}
out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->sequence, SEQ_ENBRESEL);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->sync_params, ASYNC_PARAMS);
/*
* Find out who reselected us.
*/
if (in_8(&mr->fifo_count) == 0) {
printk(KERN_ERR "mesh: reselection but nothing in fifo?\n");
ms->conn_tgt = ms->host->this_id;
goto bogus;
}
/* get the last byte in the fifo */
do {
b = in_8(&mr->fifo);
dlog(ms, "reseldata %x", b);
} while (in_8(&mr->fifo_count));
for (t = 0; t < 8; ++t)
if ((b & (1 << t)) != 0 && t != ms->host->this_id)
break;
if (b != (1 << t) + (1 << ms->host->this_id)) {
printk(KERN_ERR "mesh: bad reselection data %x\n", b);
ms->conn_tgt = ms->host->this_id;
goto bogus;
}
/*
* Set up to continue with that target's transfer.
*/
ms->conn_tgt = t;
tp = &ms->tgts[t];
out_8(&mr->sync_params, tp->sync_params);
if (ALLOW_DEBUG(t)) {
printk(KERN_DEBUG "mesh: reselected by target %d\n", t);
printk(KERN_DEBUG "mesh: saved_ptr=%x goes_out=%d cmd=%p\n",
tp->saved_ptr, tp->data_goes_out, tp->current_req);
}
ms->current_req = tp->current_req;
if (tp->current_req == NULL) {
printk(KERN_ERR "mesh: reselected by tgt %d but no cmd!\n", t);
goto bogus;
}
ms->data_ptr = tp->saved_ptr;
dlog(ms, "resel prev tgt=%d", prev);
dlog(ms, "resel err/exc=%.4x", MKWORD(0, 0, mr->error, mr->exception));
start_phase(ms);
return;
bogus:
dumplog(ms, ms->conn_tgt);
dumpslog(ms);
ms->data_ptr = 0;
ms->aborting = 1;
start_phase(ms);
}
static void do_abort(struct mesh_state *ms)
{
ms->msgout[0] = ABORT;
ms->n_msgout = 1;
ms->aborting = 1;
ms->stat = DID_ABORT;
dlog(ms, "abort", 0);
}
static void handle_reset(struct mesh_state *ms)
{
int tgt;
struct mesh_target *tp;
struct scsi_cmnd *cmd;
volatile struct mesh_regs __iomem *mr = ms->mesh;
for (tgt = 0; tgt < 8; ++tgt) {
tp = &ms->tgts[tgt];
if ((cmd = tp->current_req) != NULL) {
set_host_byte(cmd, DID_RESET);
tp->current_req = NULL;
scsi_done(cmd);
}
ms->tgts[tgt].sdtr_state = do_sdtr;
ms->tgts[tgt].sync_params = ASYNC_PARAMS;
}
ms->current_req = NULL;
while ((cmd = ms->request_q) != NULL) {
ms->request_q = (struct scsi_cmnd *) cmd->host_scribble;
set_host_byte(cmd, DID_RESET);
scsi_done(cmd);
}
ms->phase = idle;
ms->msgphase = msg_none;
out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
out_8(&mr->sequence, SEQ_FLUSHFIFO);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->sync_params, ASYNC_PARAMS);
out_8(&mr->sequence, SEQ_ENBRESEL);
}
static irqreturn_t do_mesh_interrupt(int irq, void *dev_id)
{
unsigned long flags;
struct mesh_state *ms = dev_id;
struct Scsi_Host *dev = ms->host;
spin_lock_irqsave(dev->host_lock, flags);
mesh_interrupt(ms);
spin_unlock_irqrestore(dev->host_lock, flags);
return IRQ_HANDLED;
}
static void handle_error(struct mesh_state *ms)
{
int err, exc, count;
volatile struct mesh_regs __iomem *mr = ms->mesh;
err = in_8(&mr->error);
exc = in_8(&mr->exception);
out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
dlog(ms, "error err/exc/fc/cl=%.8x",
MKWORD(err, exc, mr->fifo_count, mr->count_lo));
if (err & ERR_SCSIRESET) {
/* SCSI bus was reset */
printk(KERN_INFO "mesh: SCSI bus reset detected: "
"waiting for end...");
while ((in_8(&mr->bus_status1) & BS1_RST) != 0)
udelay(1);
printk("done\n");
if (ms->dma_started)
halt_dma(ms);
handle_reset(ms);
/* request_q is empty, no point in mesh_start() */
return;
}
if (err & ERR_UNEXPDISC) {
/* Unexpected disconnect */
if (exc & EXC_RESELECTED) {
reselected(ms);
return;
}
if (!ms->aborting) {
printk(KERN_WARNING "mesh: target %d aborted\n",
ms->conn_tgt);
dumplog(ms, ms->conn_tgt);
dumpslog(ms);
}
out_8(&mr->interrupt, INT_CMDDONE);
ms->stat = DID_ABORT;
mesh_done(ms, 1);
return;
}
if (err & ERR_PARITY) {
if (ms->msgphase == msg_in) {
printk(KERN_ERR "mesh: msg parity error, target %d\n",
ms->conn_tgt);
ms->msgout[0] = MSG_PARITY_ERROR;
ms->n_msgout = 1;
ms->msgphase = msg_in_bad;
cmd_complete(ms);
return;
}
if (ms->stat == DID_OK) {
printk(KERN_ERR "mesh: parity error, target %d\n",
ms->conn_tgt);
ms->stat = DID_PARITY;
}
count = (mr->count_hi << 8) + mr->count_lo;
if (count == 0) {
cmd_complete(ms);
} else {
/* reissue the data transfer command */
out_8(&mr->sequence, mr->sequence);
}
return;
}
if (err & ERR_SEQERR) {
if (exc & EXC_RESELECTED) {
/* This can happen if we issue a command to
get the bus just after the target reselects us. */
static int mesh_resel_seqerr;
mesh_resel_seqerr++;
reselected(ms);
return;
}
if (exc == EXC_PHASEMM) {
static int mesh_phasemm_seqerr;
mesh_phasemm_seqerr++;
phase_mismatch(ms);
return;
}
printk(KERN_ERR "mesh: sequence error (err=%x exc=%x)\n",
err, exc);
} else {
printk(KERN_ERR "mesh: unknown error %x (exc=%x)\n", err, exc);
}
mesh_dump_regs(ms);
dumplog(ms, ms->conn_tgt);
if (ms->phase > selecting && (in_8(&mr->bus_status1) & BS1_BSY)) {
/* try to do what the target wants */
do_abort(ms);
phase_mismatch(ms);
return;
}
ms->stat = DID_ERROR;
mesh_done(ms, 1);
}
static void handle_exception(struct mesh_state *ms)
{
int exc;
volatile struct mesh_regs __iomem *mr = ms->mesh;
exc = in_8(&mr->exception);
out_8(&mr->interrupt, INT_EXCEPTION | INT_CMDDONE);
if (exc & EXC_RESELECTED) {
static int mesh_resel_exc;
mesh_resel_exc++;
reselected(ms);
} else if (exc == EXC_ARBLOST) {
printk(KERN_DEBUG "mesh: lost arbitration\n");
ms->stat = DID_BUS_BUSY;
mesh_done(ms, 1);
} else if (exc == EXC_SELTO) {
/* selection timed out */
ms->stat = DID_BAD_TARGET;
mesh_done(ms, 1);
} else if (exc == EXC_PHASEMM) {
/* target wants to do something different:
find out what it wants and do it. */
phase_mismatch(ms);
} else {
printk(KERN_ERR "mesh: can't cope with exception %x\n", exc);
mesh_dump_regs(ms);
dumplog(ms, ms->conn_tgt);
do_abort(ms);
phase_mismatch(ms);
}
}
static void handle_msgin(struct mesh_state *ms)
{
int i, code;
struct scsi_cmnd *cmd = ms->current_req;
struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
if (ms->n_msgin == 0)
return;
code = ms->msgin[0];
if (ALLOW_DEBUG(ms->conn_tgt)) {
printk(KERN_DEBUG "got %d message bytes:", ms->n_msgin);
for (i = 0; i < ms->n_msgin; ++i)
printk(" %x", ms->msgin[i]);
printk("\n");
}
dlog(ms, "msgin msg=%.8x",
MKWORD(ms->n_msgin, code, ms->msgin[1], ms->msgin[2]));
ms->expect_reply = 0;
ms->n_msgout = 0;
if (ms->n_msgin < msgin_length(ms))
goto reject;
if (cmd)
mesh_priv(cmd)->message = code;
switch (code) {
case COMMAND_COMPLETE:
break;
case EXTENDED_MESSAGE:
switch (ms->msgin[2]) {
case EXTENDED_MODIFY_DATA_POINTER:
ms->data_ptr += (ms->msgin[3] << 24) + ms->msgin[6]
+ (ms->msgin[4] << 16) + (ms->msgin[5] << 8);
break;
case EXTENDED_SDTR:
if (tp->sdtr_state != sdtr_sent) {
/* reply with an SDTR */
add_sdtr_msg(ms);
/* limit period to at least his value,
offset to no more than his */
if (ms->msgout[3] < ms->msgin[3])
ms->msgout[3] = ms->msgin[3];
if (ms->msgout[4] > ms->msgin[4])
ms->msgout[4] = ms->msgin[4];
set_sdtr(ms, ms->msgout[3], ms->msgout[4]);
ms->msgphase = msg_out;
} else {
set_sdtr(ms, ms->msgin[3], ms->msgin[4]);
}
break;
default:
goto reject;
}
break;
case SAVE_POINTERS:
tp->saved_ptr = ms->data_ptr;
break;
case RESTORE_POINTERS:
ms->data_ptr = tp->saved_ptr;
break;
case DISCONNECT:
ms->phase = disconnecting;
break;
case ABORT:
break;
case MESSAGE_REJECT:
if (tp->sdtr_state == sdtr_sent)
set_sdtr(ms, 0, 0);
break;
case NOP:
break;
default:
if (IDENTIFY_BASE <= code && code <= IDENTIFY_BASE + 7) {
if (cmd == NULL) {
do_abort(ms);
ms->msgphase = msg_out;
} else if (code != cmd->device->lun + IDENTIFY_BASE) {
printk(KERN_WARNING "mesh: lun mismatch "
"(%d != %llu) on reselection from "
"target %d\n", code - IDENTIFY_BASE,
cmd->device->lun, ms->conn_tgt);
}
break;
}
goto reject;
}
return;
reject:
printk(KERN_WARNING "mesh: rejecting message from target %d:",
ms->conn_tgt);
for (i = 0; i < ms->n_msgin; ++i)
printk(" %x", ms->msgin[i]);
printk("\n");
ms->msgout[0] = MESSAGE_REJECT;
ms->n_msgout = 1;
ms->msgphase = msg_out;
}
/*
* Set up DMA commands for transferring data.
*/
static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd)
{
int i, dma_cmd, total, off, dtot;
struct scatterlist *scl;
struct dbdma_cmd *dcmds;
dma_cmd = ms->tgts[ms->conn_tgt].data_goes_out?
OUTPUT_MORE: INPUT_MORE;
dcmds = ms->dma_cmds;
dtot = 0;
if (cmd) {
int nseg;
mesh_priv(cmd)->this_residual = scsi_bufflen(cmd);
nseg = scsi_dma_map(cmd);
BUG_ON(nseg < 0);
if (nseg) {
total = 0;
off = ms->data_ptr;
scsi_for_each_sg(cmd, scl, nseg, i) {
u32 dma_addr = sg_dma_address(scl);
u32 dma_len = sg_dma_len(scl);
total += scl->length;
if (off >= dma_len) {
off -= dma_len;
continue;
}
if (dma_len > 0xffff)
panic("mesh: scatterlist element >= 64k");
dcmds->req_count = cpu_to_le16(dma_len - off);
dcmds->command = cpu_to_le16(dma_cmd);
dcmds->phy_addr = cpu_to_le32(dma_addr + off);
dcmds->xfer_status = 0;
++dcmds;
dtot += dma_len - off;
off = 0;
}
}
}
if (dtot == 0) {
/* Either the target has overrun our buffer,
or the caller didn't provide a buffer. */
static char mesh_extra_buf[64];
dtot = sizeof(mesh_extra_buf);
dcmds->req_count = cpu_to_le16(dtot);
dcmds->phy_addr = cpu_to_le32(virt_to_phys(mesh_extra_buf));
dcmds->xfer_status = 0;
++dcmds;
}
dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
dcmds[-1].command = cpu_to_le16(dma_cmd);
memset(dcmds, 0, sizeof(*dcmds));
dcmds->command = cpu_to_le16(DBDMA_STOP);
ms->dma_count = dtot;
}
static void halt_dma(struct mesh_state *ms)
{
volatile struct dbdma_regs __iomem *md = ms->dma;
volatile struct mesh_regs __iomem *mr = ms->mesh;
struct scsi_cmnd *cmd = ms->current_req;
int t, nb;
if (!ms->tgts[ms->conn_tgt].data_goes_out) {
/* wait a little while until the fifo drains */
t = 50;
while (t > 0 && in_8(&mr->fifo_count) != 0
&& (in_le32(&md->status) & ACTIVE) != 0) {
--t;
udelay(1);
}
}
out_le32(&md->control, RUN << 16); /* turn off RUN bit */
nb = (mr->count_hi << 8) + mr->count_lo;
dlog(ms, "halt_dma fc/count=%.6x",
MKWORD(0, mr->fifo_count, 0, nb));
if (ms->tgts[ms->conn_tgt].data_goes_out)
nb += mr->fifo_count;
/* nb is the number of bytes not yet transferred
to/from the target. */
ms->data_ptr -= nb;
dlog(ms, "data_ptr %x", ms->data_ptr);
if (ms->data_ptr < 0) {
printk(KERN_ERR "mesh: halt_dma: data_ptr=%d (nb=%d, ms=%p)\n",
ms->data_ptr, nb, ms);
ms->data_ptr = 0;
#ifdef MESH_DBG
dumplog(ms, ms->conn_tgt);
dumpslog(ms);
#endif /* MESH_DBG */
} else if (cmd && scsi_bufflen(cmd) &&
ms->data_ptr > scsi_bufflen(cmd)) {
printk(KERN_DEBUG "mesh: target %d overrun, "
"data_ptr=%x total=%x goes_out=%d\n",
ms->conn_tgt, ms->data_ptr, scsi_bufflen(cmd),
ms->tgts[ms->conn_tgt].data_goes_out);
}
if (cmd)
scsi_dma_unmap(cmd);
ms->dma_started = 0;
}
static void phase_mismatch(struct mesh_state *ms)
{
volatile struct mesh_regs __iomem *mr = ms->mesh;
int phase;
dlog(ms, "phasemm ch/cl/seq/fc=%.8x",
MKWORD(mr->count_hi, mr->count_lo, mr->sequence, mr->fifo_count));
phase = in_8(&mr->bus_status0) & BS0_PHASE;
if (ms->msgphase == msg_out_xxx && phase == BP_MSGOUT) {
/* output the last byte of the message, without ATN */
out_8(&mr->count_lo, 1);
out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->fifo, ms->msgout[ms->n_msgout-1]);
ms->msgphase = msg_out_last;
return;
}
if (ms->msgphase == msg_in) {
get_msgin(ms);
if (ms->n_msgin)
handle_msgin(ms);
}
if (ms->dma_started)
halt_dma(ms);
if (mr->fifo_count) {
out_8(&mr->sequence, SEQ_FLUSHFIFO);
mesh_flush_io(mr);
udelay(1);
}
ms->msgphase = msg_none;
switch (phase) {
case BP_DATAIN:
ms->tgts[ms->conn_tgt].data_goes_out = 0;
ms->phase = dataing;
break;
case BP_DATAOUT:
ms->tgts[ms->conn_tgt].data_goes_out = 1;
ms->phase = dataing;
break;
case BP_COMMAND:
ms->phase = commanding;
break;
case BP_STATUS:
ms->phase = statusing;
break;
case BP_MSGIN:
ms->msgphase = msg_in;
ms->n_msgin = 0;
break;
case BP_MSGOUT:
ms->msgphase = msg_out;
if (ms->n_msgout == 0) {
if (ms->aborting) {
do_abort(ms);
} else {
if (ms->last_n_msgout == 0) {
printk(KERN_DEBUG
"mesh: no msg to repeat\n");
ms->msgout[0] = NOP;
ms->last_n_msgout = 1;
}
ms->n_msgout = ms->last_n_msgout;
}
}
break;
default:
printk(KERN_DEBUG "mesh: unknown scsi phase %x\n", phase);
ms->stat = DID_ERROR;
mesh_done(ms, 1);
return;
}
start_phase(ms);
}
static void cmd_complete(struct mesh_state *ms)
{
volatile struct mesh_regs __iomem *mr = ms->mesh;
struct scsi_cmnd *cmd = ms->current_req;
struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
int seq, n, t;
dlog(ms, "cmd_complete fc=%x", mr->fifo_count);
seq = use_active_neg + (ms->n_msgout? SEQ_ATN: 0);
switch (ms->msgphase) {
case msg_out_xxx:
/* huh? we expected a phase mismatch */
ms->n_msgin = 0;
ms->msgphase = msg_in;
fallthrough;
case msg_in:
/* should have some message bytes in fifo */
get_msgin(ms);
n = msgin_length(ms);
if (ms->n_msgin < n) {
out_8(&mr->count_lo, n - ms->n_msgin);
out_8(&mr->sequence, SEQ_MSGIN + seq);
} else {
ms->msgphase = msg_none;
handle_msgin(ms);
start_phase(ms);
}
break;
case msg_in_bad:
out_8(&mr->sequence, SEQ_FLUSHFIFO);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->count_lo, 1);
out_8(&mr->sequence, SEQ_MSGIN + SEQ_ATN + use_active_neg);
break;
case msg_out:
/*
* To get the right timing on ATN wrt ACK, we have
* to get the MESH to drop ACK, wait until REQ gets
* asserted, then drop ATN. To do this we first
* issue a SEQ_MSGOUT with ATN and wait for REQ,
* then change the command to a SEQ_MSGOUT w/o ATN.
* If we don't see REQ in a reasonable time, we
* change the command to SEQ_MSGIN with ATN,
* wait for the phase mismatch interrupt, then
* issue the SEQ_MSGOUT without ATN.
*/
out_8(&mr->count_lo, 1);
out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg + SEQ_ATN);
t = 30; /* wait up to 30us */
while ((in_8(&mr->bus_status0) & BS0_REQ) == 0 && --t >= 0)
udelay(1);
dlog(ms, "last_mbyte err/exc/fc/cl=%.8x",
MKWORD(mr->error, mr->exception,
mr->fifo_count, mr->count_lo));
if (in_8(&mr->interrupt) & (INT_ERROR | INT_EXCEPTION)) {
/* whoops, target didn't do what we expected */
ms->last_n_msgout = ms->n_msgout;
ms->n_msgout = 0;
if (in_8(&mr->interrupt) & INT_ERROR) {
printk(KERN_ERR "mesh: error %x in msg_out\n",
in_8(&mr->error));
handle_error(ms);
return;
}
if (in_8(&mr->exception) != EXC_PHASEMM)
printk(KERN_ERR "mesh: exc %x in msg_out\n",
in_8(&mr->exception));
else
printk(KERN_DEBUG "mesh: bs0=%x in msg_out\n",
in_8(&mr->bus_status0));
handle_exception(ms);
return;
}
if (in_8(&mr->bus_status0) & BS0_REQ) {
out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->fifo, ms->msgout[ms->n_msgout-1]);
ms->msgphase = msg_out_last;
} else {
out_8(&mr->sequence, SEQ_MSGIN + use_active_neg + SEQ_ATN);
ms->msgphase = msg_out_xxx;
}
break;
case msg_out_last:
ms->last_n_msgout = ms->n_msgout;
ms->n_msgout = 0;
ms->msgphase = ms->expect_reply? msg_in: msg_none;
start_phase(ms);
break;
case msg_none:
switch (ms->phase) {
case idle:
printk(KERN_ERR "mesh: interrupt in idle phase?\n");
dumpslog(ms);
return;
case selecting:
dlog(ms, "Selecting phase at command completion",0);
ms->msgout[0] = IDENTIFY(ALLOW_RESEL(ms->conn_tgt),
(cmd? cmd->device->lun: 0));
ms->n_msgout = 1;
ms->expect_reply = 0;
if (ms->aborting) {
ms->msgout[0] = ABORT;
ms->n_msgout++;
} else if (tp->sdtr_state == do_sdtr) {
/* add SDTR message */
add_sdtr_msg(ms);
ms->expect_reply = 1;
tp->sdtr_state = sdtr_sent;
}
ms->msgphase = msg_out;
/*
* We need to wait for REQ before dropping ATN.
* We wait for at most 30us, then fall back to
* a scheme where we issue a SEQ_COMMAND with ATN,
* which will give us a phase mismatch interrupt
* when REQ does come, and then we send the message.
*/
t = 230; /* wait up to 230us */
while ((in_8(&mr->bus_status0) & BS0_REQ) == 0) {
if (--t < 0) {
dlog(ms, "impatient for req", ms->n_msgout);
ms->msgphase = msg_none;
break;
}
udelay(1);
}
break;
case dataing:
if (ms->dma_count != 0) {
start_phase(ms);
return;
}
/*
* We can get a phase mismatch here if the target
* changes to the status phase, even though we have
* had a command complete interrupt. Then, if we
* issue the SEQ_STATUS command, we'll get a sequence
* error interrupt. Which isn't so bad except that
* occasionally the mesh actually executes the
* SEQ_STATUS *as well as* giving us the sequence
* error and phase mismatch exception.
*/
out_8(&mr->sequence, 0);
out_8(&mr->interrupt,
INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
halt_dma(ms);
break;
case statusing:
if (cmd) {
struct mesh_cmd_priv *mcmd = mesh_priv(cmd);
mcmd->status = mr->fifo;
if (DEBUG_TARGET(cmd))
printk(KERN_DEBUG "mesh: status is %x\n",
mcmd->status);
}
ms->msgphase = msg_in;
break;
case busfreeing:
mesh_done(ms, 1);
return;
case disconnecting:
ms->current_req = NULL;
ms->phase = idle;
mesh_start(ms);
return;
default:
break;
}
++ms->phase;
start_phase(ms);
break;
}
}
/*
* Called by midlayer with host locked to queue a new
* request
*/
static int mesh_queue_lck(struct scsi_cmnd *cmd)
{
struct mesh_state *ms;
cmd->host_scribble = NULL;
ms = (struct mesh_state *) cmd->device->host->hostdata;
if (ms->request_q == NULL)
ms->request_q = cmd;
else
ms->request_qtail->host_scribble = (void *) cmd;
ms->request_qtail = cmd;
if (ms->phase == idle)
mesh_start(ms);
return 0;
}
static DEF_SCSI_QCMD(mesh_queue)
/*
* Called to handle interrupts, either call by the interrupt
* handler (do_mesh_interrupt) or by other functions in
* exceptional circumstances
*/
static void mesh_interrupt(struct mesh_state *ms)
{
volatile struct mesh_regs __iomem *mr = ms->mesh;
int intr;
#if 0
if (ALLOW_DEBUG(ms->conn_tgt))
printk(KERN_DEBUG "mesh_intr, bs0=%x int=%x exc=%x err=%x "
"phase=%d msgphase=%d\n", mr->bus_status0,
mr->interrupt, mr->exception, mr->error,
ms->phase, ms->msgphase);
#endif
while ((intr = in_8(&mr->interrupt)) != 0) {
dlog(ms, "interrupt intr/err/exc/seq=%.8x",
MKWORD(intr, mr->error, mr->exception, mr->sequence));
if (intr & INT_ERROR) {
handle_error(ms);
} else if (intr & INT_EXCEPTION) {
handle_exception(ms);
} else if (intr & INT_CMDDONE) {
out_8(&mr->interrupt, INT_CMDDONE);
cmd_complete(ms);
}
}
}
/* Todo: here we can at least try to remove the command from the
* queue if it isn't connected yet, and for pending command, assert
* ATN until the bus gets freed.
*/
static int mesh_abort(struct scsi_cmnd *cmd)
{
struct mesh_state *ms = (struct mesh_state *) cmd->device->host->hostdata;
printk(KERN_DEBUG "mesh_abort(%p)\n", cmd);
mesh_dump_regs(ms);
dumplog(ms, cmd->device->id);
dumpslog(ms);
return FAILED;
}
/*
* Called by the midlayer with the lock held to reset the
* SCSI host and bus.
* The midlayer will wait for devices to come back, we don't need
* to do that ourselves
*/
static int mesh_host_reset(struct scsi_cmnd *cmd)
{
struct mesh_state *ms = (struct mesh_state *) cmd->device->host->hostdata;
volatile struct mesh_regs __iomem *mr = ms->mesh;
volatile struct dbdma_regs __iomem *md = ms->dma;
unsigned long flags;
printk(KERN_DEBUG "mesh_host_reset\n");
spin_lock_irqsave(ms->host->host_lock, flags);
if (ms->dma_started)
halt_dma(ms);
/* Reset the controller & dbdma channel */
out_le32(&md->control, (RUN|PAUSE|FLUSH|WAKE) << 16); /* stop dma */
out_8(&mr->exception, 0xff); /* clear all exception bits */
out_8(&mr->error, 0xff); /* clear all error bits */
out_8(&mr->sequence, SEQ_RESETMESH);
mesh_flush_io(mr);
udelay(1);
out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
out_8(&mr->source_id, ms->host->this_id);
out_8(&mr->sel_timeout, 25); /* 250ms */
out_8(&mr->sync_params, ASYNC_PARAMS);
/* Reset the bus */
out_8(&mr->bus_status1, BS1_RST); /* assert RST */
mesh_flush_io(mr);
udelay(30); /* leave it on for >= 25us */
out_8(&mr->bus_status1, 0); /* negate RST */
/* Complete pending commands */
handle_reset(ms);
spin_unlock_irqrestore(ms->host->host_lock, flags);
return SUCCESS;
}
static void set_mesh_power(struct mesh_state *ms, int state)
{
if (!machine_is(powermac))
return;
if (state) {
pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 1);
msleep(200);
} else {
pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 0);
msleep(10);
}
}
#ifdef CONFIG_PM
static int mesh_suspend(struct macio_dev *mdev, pm_message_t mesg)
{
struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
unsigned long flags;
switch (mesg.event) {
case PM_EVENT_SUSPEND:
case PM_EVENT_HIBERNATE:
case PM_EVENT_FREEZE:
break;
default:
return 0;
}
if (ms->phase == sleeping)
return 0;
scsi_block_requests(ms->host);
spin_lock_irqsave(ms->host->host_lock, flags);
while(ms->phase != idle) {
spin_unlock_irqrestore(ms->host->host_lock, flags);
msleep(10);
spin_lock_irqsave(ms->host->host_lock, flags);
}
ms->phase = sleeping;
spin_unlock_irqrestore(ms->host->host_lock, flags);
disable_irq(ms->meshintr);
set_mesh_power(ms, 0);
return 0;
}
static int mesh_resume(struct macio_dev *mdev)
{
struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
unsigned long flags;
if (ms->phase != sleeping)
return 0;
set_mesh_power(ms, 1);
mesh_init(ms);
spin_lock_irqsave(ms->host->host_lock, flags);
mesh_start(ms);
spin_unlock_irqrestore(ms->host->host_lock, flags);
enable_irq(ms->meshintr);
scsi_unblock_requests(ms->host);
return 0;
}
#endif /* CONFIG_PM */
/*
* If we leave drives set for synchronous transfers (especially
* CDROMs), and reboot to MacOS, it gets confused, poor thing.
* So, on reboot we reset the SCSI bus.
*/
static int mesh_shutdown(struct macio_dev *mdev)
{
struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
volatile struct mesh_regs __iomem *mr;
unsigned long flags;
printk(KERN_INFO "resetting MESH scsi bus(es)\n");
spin_lock_irqsave(ms->host->host_lock, flags);
mr = ms->mesh;
out_8(&mr->intr_mask, 0);
out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
out_8(&mr->bus_status1, BS1_RST);
mesh_flush_io(mr);
udelay(30);
out_8(&mr->bus_status1, 0);
spin_unlock_irqrestore(ms->host->host_lock, flags);
return 0;
}
static const struct scsi_host_template mesh_template = {
.proc_name = "mesh",
.name = "MESH",
.queuecommand = mesh_queue,
.eh_abort_handler = mesh_abort,
.eh_host_reset_handler = mesh_host_reset,
.can_queue = 20,
.this_id = 7,
.sg_tablesize = SG_ALL,
.cmd_per_lun = 2,
.max_segment_size = 65535,
.cmd_size = sizeof(struct mesh_cmd_priv),
};
static int mesh_probe(struct macio_dev *mdev, const struct of_device_id *match)
{
struct device_node *mesh = macio_get_of_node(mdev);
struct pci_dev* pdev = macio_get_pci_dev(mdev);
int tgt, minper;
const int *cfp;
struct mesh_state *ms;
struct Scsi_Host *mesh_host;
void *dma_cmd_space;
dma_addr_t dma_cmd_bus;
switch (mdev->bus->chip->type) {
case macio_heathrow:
case macio_gatwick:
case macio_paddington:
use_active_neg = 0;
break;
default:
use_active_neg = SEQ_ACTIVE_NEG;
}
if (macio_resource_count(mdev) != 2 || macio_irq_count(mdev) != 2) {
printk(KERN_ERR "mesh: expected 2 addrs and 2 intrs"
" (got %d,%d)\n", macio_resource_count(mdev),
macio_irq_count(mdev));
return -ENODEV;
}
if (macio_request_resources(mdev, "mesh") != 0) {
printk(KERN_ERR "mesh: unable to request memory resources");
return -EBUSY;
}
mesh_host = scsi_host_alloc(&mesh_template, sizeof(struct mesh_state));
if (mesh_host == NULL) {
printk(KERN_ERR "mesh: couldn't register host");
goto out_release;
}
mesh_host->base = macio_resource_start(mdev, 0);
mesh_host->irq = macio_irq(mdev, 0);
ms = (struct mesh_state *) mesh_host->hostdata;
macio_set_drvdata(mdev, ms);
ms->host = mesh_host;
ms->mdev = mdev;
ms->pdev = pdev;
ms->mesh = ioremap(macio_resource_start(mdev, 0), 0x1000);
if (ms->mesh == NULL) {
printk(KERN_ERR "mesh: can't map registers\n");
goto out_free;
}
ms->dma = ioremap(macio_resource_start(mdev, 1), 0x1000);
if (ms->dma == NULL) {
printk(KERN_ERR "mesh: can't map registers\n");
iounmap(ms->mesh);
goto out_free;
}
ms->meshintr = macio_irq(mdev, 0);
ms->dmaintr = macio_irq(mdev, 1);
/* Space for dma command list: +1 for stop command,
* +1 to allow for aligning.
*/
ms->dma_cmd_size = (mesh_host->sg_tablesize + 2) * sizeof(struct dbdma_cmd);
/* We use the PCI APIs for now until the generic one gets fixed
* enough or until we get some macio-specific versions
*/
dma_cmd_space = dma_alloc_coherent(&macio_get_pci_dev(mdev)->dev,
ms->dma_cmd_size, &dma_cmd_bus,
GFP_KERNEL);
if (dma_cmd_space == NULL) {
printk(KERN_ERR "mesh: can't allocate DMA table\n");
goto out_unmap;
}
ms->dma_cmds = (struct dbdma_cmd *) DBDMA_ALIGN(dma_cmd_space);
ms->dma_cmd_space = dma_cmd_space;
ms->dma_cmd_bus = dma_cmd_bus + ((unsigned long)ms->dma_cmds)
- (unsigned long)dma_cmd_space;
ms->current_req = NULL;
for (tgt = 0; tgt < 8; ++tgt) {
ms->tgts[tgt].sdtr_state = do_sdtr;
ms->tgts[tgt].sync_params = ASYNC_PARAMS;
ms->tgts[tgt].current_req = NULL;
}
if ((cfp = of_get_property(mesh, "clock-frequency", NULL)))
ms->clk_freq = *cfp;
else {
printk(KERN_INFO "mesh: assuming 50MHz clock frequency\n");
ms->clk_freq = 50000000;
}
/* The maximum sync rate is clock / 5; increase
* mesh_sync_period if necessary.
*/
minper = 1000000000 / (ms->clk_freq / 5); /* ns */
if (mesh_sync_period < minper)
mesh_sync_period = minper;
/* Power up the chip */
set_mesh_power(ms, 1);
/* Set it up */
mesh_init(ms);
/* Request interrupt */
if (request_irq(ms->meshintr, do_mesh_interrupt, 0, "MESH", ms)) {
printk(KERN_ERR "MESH: can't get irq %d\n", ms->meshintr);
goto out_shutdown;
}
/* Add scsi host & scan */
if (scsi_add_host(mesh_host, &mdev->ofdev.dev))
goto out_release_irq;
scsi_scan_host(mesh_host);
return 0;
out_release_irq:
free_irq(ms->meshintr, ms);
out_shutdown:
/* shutdown & reset bus in case of error or macos can be confused
* at reboot if the bus was set to synchronous mode already
*/
mesh_shutdown(mdev);
set_mesh_power(ms, 0);
dma_free_coherent(&macio_get_pci_dev(mdev)->dev, ms->dma_cmd_size,
ms->dma_cmd_space, ms->dma_cmd_bus);
out_unmap:
iounmap(ms->dma);
iounmap(ms->mesh);
out_free:
scsi_host_put(mesh_host);
out_release:
macio_release_resources(mdev);
return -ENODEV;
}
static int mesh_remove(struct macio_dev *mdev)
{
struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
struct Scsi_Host *mesh_host = ms->host;
scsi_remove_host(mesh_host);
free_irq(ms->meshintr, ms);
/* Reset scsi bus */
mesh_shutdown(mdev);
/* Shut down chip & termination */
set_mesh_power(ms, 0);
/* Unmap registers & dma controller */
iounmap(ms->mesh);
iounmap(ms->dma);
/* Free DMA commands memory */
dma_free_coherent(&macio_get_pci_dev(mdev)->dev, ms->dma_cmd_size,
ms->dma_cmd_space, ms->dma_cmd_bus);
/* Release memory resources */
macio_release_resources(mdev);
scsi_host_put(mesh_host);
return 0;
}
static struct of_device_id mesh_match[] =
{
{
.name = "mesh",
},
{
.type = "scsi",
.compatible = "chrp,mesh0"
},
{},
};
MODULE_DEVICE_TABLE (of, mesh_match);
static struct macio_driver mesh_driver =
{
.driver = {
.name = "mesh",
.owner = THIS_MODULE,
.of_match_table = mesh_match,
},
.probe = mesh_probe,
.remove = mesh_remove,
.shutdown = mesh_shutdown,
#ifdef CONFIG_PM
.suspend = mesh_suspend,
.resume = mesh_resume,
#endif
};
static int __init init_mesh(void)
{
/* Calculate sync rate from module parameters */
if (sync_rate > 10)
sync_rate = 10;
if (sync_rate > 0) {
printk(KERN_INFO "mesh: configured for synchronous %d MB/s\n", sync_rate);
mesh_sync_period = 1000 / sync_rate; /* ns */
mesh_sync_offset = 15;
} else
printk(KERN_INFO "mesh: configured for asynchronous\n");
return macio_register_driver(&mesh_driver);
}
static void __exit exit_mesh(void)
{
return macio_unregister_driver(&mesh_driver);
}
module_init(init_mesh);
module_exit(exit_mesh);