568 lines
15 KiB
C
568 lines
15 KiB
C
/*
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* SCSI low-level driver for the 53c94 SCSI bus adaptor found
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* on Power Macintosh computers, controlling the external SCSI chain.
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* We assume the 53c94 is connected to a DBDMA (descriptor-based DMA)
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* controller.
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*
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* Paul Mackerras, August 1996.
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* Copyright (C) 1996 Paul Mackerras.
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*/
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#include <linux/kernel.h>
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#include <linux/delay.h>
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#include <linux/types.h>
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#include <linux/string.h>
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#include <linux/slab.h>
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#include <linux/blkdev.h>
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#include <linux/proc_fs.h>
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#include <linux/stat.h>
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#include <linux/spinlock.h>
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#include <linux/interrupt.h>
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#include <asm/dbdma.h>
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#include <asm/io.h>
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#include <asm/pgtable.h>
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#include <asm/prom.h>
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#include <asm/system.h>
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#include <asm/pci-bridge.h>
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#include <asm/macio.h>
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#include <scsi/scsi.h>
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#include <scsi/scsi_cmnd.h>
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#include <scsi/scsi_device.h>
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#include <scsi/scsi_host.h>
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#include "mac53c94.h"
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enum fsc_phase {
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idle,
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selecting,
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dataing,
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completing,
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busfreeing,
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};
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struct fsc_state {
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struct mac53c94_regs __iomem *regs;
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int intr;
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struct dbdma_regs __iomem *dma;
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int dmaintr;
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int clk_freq;
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struct Scsi_Host *host;
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struct scsi_cmnd *request_q;
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struct scsi_cmnd *request_qtail;
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struct scsi_cmnd *current_req; /* req we're currently working on */
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enum fsc_phase phase; /* what we're currently trying to do */
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struct dbdma_cmd *dma_cmds; /* space for dbdma commands, aligned */
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void *dma_cmd_space;
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struct pci_dev *pdev;
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dma_addr_t dma_addr;
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struct macio_dev *mdev;
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};
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static void mac53c94_init(struct fsc_state *);
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static void mac53c94_start(struct fsc_state *);
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static void mac53c94_interrupt(int, void *);
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static irqreturn_t do_mac53c94_interrupt(int, void *);
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static void cmd_done(struct fsc_state *, int result);
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static void set_dma_cmds(struct fsc_state *, struct scsi_cmnd *);
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static int mac53c94_queue(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
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{
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struct fsc_state *state;
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#if 0
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if (cmd->sc_data_direction == DMA_TO_DEVICE) {
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int i;
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printk(KERN_DEBUG "mac53c94_queue %p: command is", cmd);
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for (i = 0; i < cmd->cmd_len; ++i)
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printk(KERN_CONT " %.2x", cmd->cmnd[i]);
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printk(KERN_CONT "\n");
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printk(KERN_DEBUG "use_sg=%d request_bufflen=%d request_buffer=%p\n",
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scsi_sg_count(cmd), scsi_bufflen(cmd), scsi_sglist(cmd));
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}
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#endif
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cmd->scsi_done = done;
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cmd->host_scribble = NULL;
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state = (struct fsc_state *) cmd->device->host->hostdata;
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if (state->request_q == NULL)
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state->request_q = cmd;
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else
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state->request_qtail->host_scribble = (void *) cmd;
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state->request_qtail = cmd;
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if (state->phase == idle)
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mac53c94_start(state);
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return 0;
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}
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static int mac53c94_host_reset(struct scsi_cmnd *cmd)
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{
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struct fsc_state *state = (struct fsc_state *) cmd->device->host->hostdata;
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struct mac53c94_regs __iomem *regs = state->regs;
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struct dbdma_regs __iomem *dma = state->dma;
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unsigned long flags;
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spin_lock_irqsave(cmd->device->host->host_lock, flags);
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writel((RUN|PAUSE|FLUSH|WAKE) << 16, &dma->control);
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writeb(CMD_SCSI_RESET, ®s->command); /* assert RST */
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udelay(100); /* leave it on for a while (>= 25us) */
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writeb(CMD_RESET, ®s->command);
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udelay(20);
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mac53c94_init(state);
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writeb(CMD_NOP, ®s->command);
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spin_unlock_irqrestore(cmd->device->host->host_lock, flags);
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return SUCCESS;
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}
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static void mac53c94_init(struct fsc_state *state)
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{
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struct mac53c94_regs __iomem *regs = state->regs;
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struct dbdma_regs __iomem *dma = state->dma;
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int x;
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writeb(state->host->this_id | CF1_PAR_ENABLE, ®s->config1);
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writeb(TIMO_VAL(250), ®s->sel_timeout); /* 250ms */
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writeb(CLKF_VAL(state->clk_freq), ®s->clk_factor);
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writeb(CF2_FEATURE_EN, ®s->config2);
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writeb(0, ®s->config3);
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writeb(0, ®s->sync_period);
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writeb(0, ®s->sync_offset);
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x = readb(®s->interrupt);
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writel((RUN|PAUSE|FLUSH|WAKE) << 16, &dma->control);
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}
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/*
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* Start the next command for a 53C94.
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* Should be called with interrupts disabled.
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*/
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static void mac53c94_start(struct fsc_state *state)
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{
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struct scsi_cmnd *cmd;
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struct mac53c94_regs __iomem *regs = state->regs;
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int i;
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if (state->phase != idle || state->current_req != NULL)
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panic("inappropriate mac53c94_start (state=%p)", state);
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if (state->request_q == NULL)
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return;
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state->current_req = cmd = state->request_q;
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state->request_q = (struct scsi_cmnd *) cmd->host_scribble;
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/* Off we go */
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writeb(0, ®s->count_lo);
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writeb(0, ®s->count_mid);
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writeb(0, ®s->count_hi);
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writeb(CMD_NOP + CMD_DMA_MODE, ®s->command);
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udelay(1);
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writeb(CMD_FLUSH, ®s->command);
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udelay(1);
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writeb(cmd->device->id, ®s->dest_id);
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writeb(0, ®s->sync_period);
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writeb(0, ®s->sync_offset);
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/* load the command into the FIFO */
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for (i = 0; i < cmd->cmd_len; ++i)
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writeb(cmd->cmnd[i], ®s->fifo);
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/* do select without ATN XXX */
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writeb(CMD_SELECT, ®s->command);
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state->phase = selecting;
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set_dma_cmds(state, cmd);
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}
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static irqreturn_t do_mac53c94_interrupt(int irq, void *dev_id)
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{
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unsigned long flags;
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struct Scsi_Host *dev = ((struct fsc_state *) dev_id)->current_req->device->host;
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spin_lock_irqsave(dev->host_lock, flags);
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mac53c94_interrupt(irq, dev_id);
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spin_unlock_irqrestore(dev->host_lock, flags);
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return IRQ_HANDLED;
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}
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static void mac53c94_interrupt(int irq, void *dev_id)
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{
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struct fsc_state *state = (struct fsc_state *) dev_id;
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struct mac53c94_regs __iomem *regs = state->regs;
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struct dbdma_regs __iomem *dma = state->dma;
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struct scsi_cmnd *cmd = state->current_req;
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int nb, stat, seq, intr;
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static int mac53c94_errors;
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/*
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* Apparently, reading the interrupt register unlatches
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* the status and sequence step registers.
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*/
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seq = readb(®s->seqstep);
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stat = readb(®s->status);
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intr = readb(®s->interrupt);
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#if 0
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printk(KERN_DEBUG "mac53c94_intr, intr=%x stat=%x seq=%x phase=%d\n",
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intr, stat, seq, state->phase);
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#endif
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if (intr & INTR_RESET) {
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/* SCSI bus was reset */
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printk(KERN_INFO "external SCSI bus reset detected\n");
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writeb(CMD_NOP, ®s->command);
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writel(RUN << 16, &dma->control); /* stop dma */
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cmd_done(state, DID_RESET << 16);
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return;
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}
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if (intr & INTR_ILL_CMD) {
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printk(KERN_ERR "53c94: invalid cmd, intr=%x stat=%x seq=%x phase=%d\n",
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intr, stat, seq, state->phase);
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cmd_done(state, DID_ERROR << 16);
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return;
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}
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if (stat & STAT_ERROR) {
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#if 0
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/* XXX these seem to be harmless? */
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printk("53c94: bad error, intr=%x stat=%x seq=%x phase=%d\n",
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intr, stat, seq, state->phase);
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#endif
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++mac53c94_errors;
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writeb(CMD_NOP + CMD_DMA_MODE, ®s->command);
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}
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if (cmd == 0) {
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printk(KERN_DEBUG "53c94: interrupt with no command active?\n");
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return;
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}
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if (stat & STAT_PARITY) {
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printk(KERN_ERR "mac53c94: parity error\n");
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cmd_done(state, DID_PARITY << 16);
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return;
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}
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switch (state->phase) {
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case selecting:
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if (intr & INTR_DISCONNECT) {
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/* selection timed out */
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cmd_done(state, DID_BAD_TARGET << 16);
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return;
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}
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if (intr != INTR_BUS_SERV + INTR_DONE) {
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printk(KERN_DEBUG "got intr %x during selection\n", intr);
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cmd_done(state, DID_ERROR << 16);
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return;
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}
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if ((seq & SS_MASK) != SS_DONE) {
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printk(KERN_DEBUG "seq step %x after command\n", seq);
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cmd_done(state, DID_ERROR << 16);
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return;
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}
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writeb(CMD_NOP, ®s->command);
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/* set DMA controller going if any data to transfer */
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if ((stat & (STAT_MSG|STAT_CD)) == 0
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&& (scsi_sg_count(cmd) > 0 || scsi_bufflen(cmd))) {
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nb = cmd->SCp.this_residual;
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if (nb > 0xfff0)
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nb = 0xfff0;
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cmd->SCp.this_residual -= nb;
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writeb(nb, ®s->count_lo);
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writeb(nb >> 8, ®s->count_mid);
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writeb(CMD_DMA_MODE + CMD_NOP, ®s->command);
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writel(virt_to_phys(state->dma_cmds), &dma->cmdptr);
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writel((RUN << 16) | RUN, &dma->control);
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writeb(CMD_DMA_MODE + CMD_XFER_DATA, ®s->command);
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state->phase = dataing;
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break;
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} else if ((stat & STAT_PHASE) == STAT_CD + STAT_IO) {
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/* up to status phase already */
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writeb(CMD_I_COMPLETE, ®s->command);
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state->phase = completing;
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} else {
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printk(KERN_DEBUG "in unexpected phase %x after cmd\n",
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stat & STAT_PHASE);
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cmd_done(state, DID_ERROR << 16);
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return;
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}
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break;
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case dataing:
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if (intr != INTR_BUS_SERV) {
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printk(KERN_DEBUG "got intr %x before status\n", intr);
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cmd_done(state, DID_ERROR << 16);
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return;
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}
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if (cmd->SCp.this_residual != 0
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&& (stat & (STAT_MSG|STAT_CD)) == 0) {
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/* Set up the count regs to transfer more */
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nb = cmd->SCp.this_residual;
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if (nb > 0xfff0)
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nb = 0xfff0;
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cmd->SCp.this_residual -= nb;
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writeb(nb, ®s->count_lo);
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writeb(nb >> 8, ®s->count_mid);
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writeb(CMD_DMA_MODE + CMD_NOP, ®s->command);
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writeb(CMD_DMA_MODE + CMD_XFER_DATA, ®s->command);
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break;
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}
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if ((stat & STAT_PHASE) != STAT_CD + STAT_IO) {
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printk(KERN_DEBUG "intr %x before data xfer complete\n", intr);
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}
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writel(RUN << 16, &dma->control); /* stop dma */
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scsi_dma_unmap(cmd);
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/* should check dma status */
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writeb(CMD_I_COMPLETE, ®s->command);
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state->phase = completing;
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break;
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case completing:
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if (intr != INTR_DONE) {
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printk(KERN_DEBUG "got intr %x on completion\n", intr);
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cmd_done(state, DID_ERROR << 16);
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return;
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}
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cmd->SCp.Status = readb(®s->fifo);
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cmd->SCp.Message = readb(®s->fifo);
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cmd->result = CMD_ACCEPT_MSG;
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writeb(CMD_ACCEPT_MSG, ®s->command);
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state->phase = busfreeing;
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break;
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case busfreeing:
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if (intr != INTR_DISCONNECT) {
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printk(KERN_DEBUG "got intr %x when expected disconnect\n", intr);
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}
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cmd_done(state, (DID_OK << 16) + (cmd->SCp.Message << 8)
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+ cmd->SCp.Status);
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break;
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default:
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printk(KERN_DEBUG "don't know about phase %d\n", state->phase);
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}
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}
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static void cmd_done(struct fsc_state *state, int result)
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{
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struct scsi_cmnd *cmd;
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cmd = state->current_req;
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if (cmd != 0) {
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cmd->result = result;
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(*cmd->scsi_done)(cmd);
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state->current_req = NULL;
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}
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state->phase = idle;
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mac53c94_start(state);
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}
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/*
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* Set up DMA commands for transferring data.
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*/
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static void set_dma_cmds(struct fsc_state *state, struct scsi_cmnd *cmd)
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{
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int i, dma_cmd, total, nseg;
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struct scatterlist *scl;
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struct dbdma_cmd *dcmds;
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dma_addr_t dma_addr;
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u32 dma_len;
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nseg = scsi_dma_map(cmd);
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BUG_ON(nseg < 0);
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if (!nseg)
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return;
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dma_cmd = cmd->sc_data_direction == DMA_TO_DEVICE ?
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OUTPUT_MORE : INPUT_MORE;
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dcmds = state->dma_cmds;
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total = 0;
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scsi_for_each_sg(cmd, scl, nseg, i) {
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dma_addr = sg_dma_address(scl);
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dma_len = sg_dma_len(scl);
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if (dma_len > 0xffff)
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panic("mac53c94: scatterlist element >= 64k");
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total += dma_len;
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st_le16(&dcmds->req_count, dma_len);
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st_le16(&dcmds->command, dma_cmd);
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st_le32(&dcmds->phy_addr, dma_addr);
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dcmds->xfer_status = 0;
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++dcmds;
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}
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dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
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st_le16(&dcmds[-1].command, dma_cmd);
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st_le16(&dcmds->command, DBDMA_STOP);
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cmd->SCp.this_residual = total;
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}
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static struct scsi_host_template mac53c94_template = {
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.proc_name = "53c94",
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.name = "53C94",
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.queuecommand = mac53c94_queue,
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.eh_host_reset_handler = mac53c94_host_reset,
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.can_queue = 1,
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.this_id = 7,
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.sg_tablesize = SG_ALL,
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.cmd_per_lun = 1,
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.use_clustering = DISABLE_CLUSTERING,
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};
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static int mac53c94_probe(struct macio_dev *mdev, const struct of_device_id *match)
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{
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struct device_node *node = macio_get_of_node(mdev);
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struct pci_dev *pdev = macio_get_pci_dev(mdev);
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struct fsc_state *state;
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struct Scsi_Host *host;
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void *dma_cmd_space;
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const unsigned char *clkprop;
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int proplen, rc = -ENODEV;
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if (macio_resource_count(mdev) != 2 || macio_irq_count(mdev) != 2) {
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printk(KERN_ERR "mac53c94: expected 2 addrs and intrs"
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" (got %d/%d)\n",
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macio_resource_count(mdev), macio_irq_count(mdev));
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return -ENODEV;
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}
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if (macio_request_resources(mdev, "mac53c94") != 0) {
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printk(KERN_ERR "mac53c94: unable to request memory resources");
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return -EBUSY;
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}
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host = scsi_host_alloc(&mac53c94_template, sizeof(struct fsc_state));
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if (host == NULL) {
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printk(KERN_ERR "mac53c94: couldn't register host");
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rc = -ENOMEM;
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goto out_release;
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}
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state = (struct fsc_state *) host->hostdata;
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macio_set_drvdata(mdev, state);
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state->host = host;
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state->pdev = pdev;
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state->mdev = mdev;
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state->regs = (struct mac53c94_regs __iomem *)
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ioremap(macio_resource_start(mdev, 0), 0x1000);
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state->intr = macio_irq(mdev, 0);
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state->dma = (struct dbdma_regs __iomem *)
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ioremap(macio_resource_start(mdev, 1), 0x1000);
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state->dmaintr = macio_irq(mdev, 1);
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if (state->regs == NULL || state->dma == NULL) {
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printk(KERN_ERR "mac53c94: ioremap failed for %s\n",
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node->full_name);
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goto out_free;
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}
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clkprop = of_get_property(node, "clock-frequency", &proplen);
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if (clkprop == NULL || proplen != sizeof(int)) {
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printk(KERN_ERR "%s: can't get clock frequency, "
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"assuming 25MHz\n", node->full_name);
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state->clk_freq = 25000000;
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} else
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state->clk_freq = *(int *)clkprop;
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/* Space for dma command list: +1 for stop command,
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* +1 to allow for aligning.
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* XXX FIXME: Use DMA consistent routines
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*/
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dma_cmd_space = kmalloc((host->sg_tablesize + 2) *
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sizeof(struct dbdma_cmd), GFP_KERNEL);
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if (dma_cmd_space == 0) {
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printk(KERN_ERR "mac53c94: couldn't allocate dma "
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"command space for %s\n", node->full_name);
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rc = -ENOMEM;
|
|
goto out_free;
|
|
}
|
|
state->dma_cmds = (struct dbdma_cmd *)DBDMA_ALIGN(dma_cmd_space);
|
|
memset(state->dma_cmds, 0, (host->sg_tablesize + 1)
|
|
* sizeof(struct dbdma_cmd));
|
|
state->dma_cmd_space = dma_cmd_space;
|
|
|
|
mac53c94_init(state);
|
|
|
|
if (request_irq(state->intr, do_mac53c94_interrupt, 0, "53C94",state)) {
|
|
printk(KERN_ERR "mac53C94: can't get irq %d for %s\n",
|
|
state->intr, node->full_name);
|
|
goto out_free_dma;
|
|
}
|
|
|
|
rc = scsi_add_host(host, &mdev->ofdev.dev);
|
|
if (rc != 0)
|
|
goto out_release_irq;
|
|
|
|
scsi_scan_host(host);
|
|
return 0;
|
|
|
|
out_release_irq:
|
|
free_irq(state->intr, state);
|
|
out_free_dma:
|
|
kfree(state->dma_cmd_space);
|
|
out_free:
|
|
if (state->dma != NULL)
|
|
iounmap(state->dma);
|
|
if (state->regs != NULL)
|
|
iounmap(state->regs);
|
|
scsi_host_put(host);
|
|
out_release:
|
|
macio_release_resources(mdev);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int mac53c94_remove(struct macio_dev *mdev)
|
|
{
|
|
struct fsc_state *fp = (struct fsc_state *)macio_get_drvdata(mdev);
|
|
struct Scsi_Host *host = fp->host;
|
|
|
|
scsi_remove_host(host);
|
|
|
|
free_irq(fp->intr, fp);
|
|
|
|
if (fp->regs)
|
|
iounmap(fp->regs);
|
|
if (fp->dma)
|
|
iounmap(fp->dma);
|
|
kfree(fp->dma_cmd_space);
|
|
|
|
scsi_host_put(host);
|
|
|
|
macio_release_resources(mdev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static struct of_device_id mac53c94_match[] =
|
|
{
|
|
{
|
|
.name = "53c94",
|
|
},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE (of, mac53c94_match);
|
|
|
|
static struct macio_driver mac53c94_driver =
|
|
{
|
|
.name = "mac53c94",
|
|
.match_table = mac53c94_match,
|
|
.probe = mac53c94_probe,
|
|
.remove = mac53c94_remove,
|
|
};
|
|
|
|
|
|
static int __init init_mac53c94(void)
|
|
{
|
|
return macio_register_driver(&mac53c94_driver);
|
|
}
|
|
|
|
static void __exit exit_mac53c94(void)
|
|
{
|
|
return macio_unregister_driver(&mac53c94_driver);
|
|
}
|
|
|
|
module_init(init_mac53c94);
|
|
module_exit(exit_mac53c94);
|
|
|
|
MODULE_DESCRIPTION("PowerMac 53c94 SCSI driver");
|
|
MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
|
|
MODULE_LICENSE("GPL");
|