dec_esp.c

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{
	struct NCR_ESP *esp = dev_get_drvdata(dev);

	free_irq(esp->irq, esp->ehost);
	esp_deallocate(esp);
	scsi_host_put(esp->ehost);
}


/************************************************************* DMA Functions */
static irqreturn_t scsi_dma_merr_int(int irq, void *dev_id)
{
	printk("Got unexpected SCSI DMA Interrupt! < ");
	printk("SCSI_DMA_MEMRDERR ");
	printk(">\n");

	return IRQ_HANDLED;
}

static irqreturn_t scsi_dma_err_int(int irq, void *dev_id)
{
	/* empty */

	return IRQ_HANDLED;
}

static irqreturn_t scsi_dma_int(int irq, void *dev_id)
{
	u32 scsi_next_ptr;

	scsi_next_ptr = ioasic_read(IO_REG_SCSI_DMA_P);

	/* next page */
	scsi_next_ptr = (((scsi_next_ptr >> 3) + PAGE_SIZE) & PAGE_MASK) << 3;
	ioasic_write(IO_REG_SCSI_DMA_BP, scsi_next_ptr);
	fast_iob();

	return IRQ_HANDLED;
}

static int dma_bytes_sent(struct NCR_ESP *esp, int fifo_count)
{
	return fifo_count;
}

static void dma_drain(struct NCR_ESP *esp)
{
	u32 nw, data0, data1, scsi_data_ptr;
	u16 *p;

	nw = ioasic_read(IO_REG_SCSI_SCR);

	/*
	 * Is there something in the dma buffers left?
	 */
	if (nw) {
		scsi_data_ptr = ioasic_read(IO_REG_SCSI_DMA_P) >> 3;
		p = phys_to_virt(scsi_data_ptr);
		switch (nw) {
		case 1:
			data0 = ioasic_read(IO_REG_SCSI_SDR0);
			p[0] = data0 & 0xffff;
			break;
		case 2:
			data0 = ioasic_read(IO_REG_SCSI_SDR0);
			p[0] = data0 & 0xffff;
			p[1] = (data0 >> 16) & 0xffff;
			break;
		case 3:
			data0 = ioasic_read(IO_REG_SCSI_SDR0);
			data1 = ioasic_read(IO_REG_SCSI_SDR1);
			p[0] = data0 & 0xffff;
			p[1] = (data0 >> 16) & 0xffff;
			p[2] = data1 & 0xffff;
			break;
		default:
			printk("Strange: %d words in dma buffer left\n", nw);
			break;
		}
	}
}

static int dma_can_transfer(struct NCR_ESP *esp, struct scsi_cmnd * sp)
{
	return sp->SCp.this_residual;
}

static void dma_dump_state(struct NCR_ESP *esp)
{
}

static void dma_init_read(struct NCR_ESP *esp, u32 vaddress, int length)
{
	u32 scsi_next_ptr, ioasic_ssr;
	unsigned long flags;

	if (vaddress & 3)
		panic("dec_esp.c: unable to handle partial word transfers, yet...");

	dma_cache_wback_inv((unsigned long) phys_to_virt(vaddress), length);

	spin_lock_irqsave(&ioasic_ssr_lock, flags);

	fast_mb();
	ioasic_ssr = ioasic_read(IO_REG_SSR);

	ioasic_ssr &= ~IO_SSR_SCSI_DMA_EN;
	ioasic_write(IO_REG_SSR, ioasic_ssr);

	fast_wmb();
	ioasic_write(IO_REG_SCSI_SCR, 0);
	ioasic_write(IO_REG_SCSI_DMA_P, vaddress << 3);

	/* prepare for next page */
	scsi_next_ptr = ((vaddress + PAGE_SIZE) & PAGE_MASK) << 3;
	ioasic_write(IO_REG_SCSI_DMA_BP, scsi_next_ptr);

	ioasic_ssr |= (IO_SSR_SCSI_DMA_DIR | IO_SSR_SCSI_DMA_EN);
	fast_wmb();
	ioasic_write(IO_REG_SSR, ioasic_ssr);

	fast_iob();
	spin_unlock_irqrestore(&ioasic_ssr_lock, flags);
}

static void dma_init_write(struct NCR_ESP *esp, u32 vaddress, int length)
{
	u32 scsi_next_ptr, ioasic_ssr;
	unsigned long flags;

	if (vaddress & 3)
		panic("dec_esp.c: unable to handle partial word transfers, yet...");

	dma_cache_wback_inv((unsigned long) phys_to_virt(vaddress), length);

	spin_lock_irqsave(&ioasic_ssr_lock, flags);

	fast_mb();
	ioasic_ssr = ioasic_read(IO_REG_SSR);

	ioasic_ssr &= ~(IO_SSR_SCSI_DMA_DIR | IO_SSR_SCSI_DMA_EN);
	ioasic_write(IO_REG_SSR, ioasic_ssr);

	fast_wmb();
	ioasic_write(IO_REG_SCSI_SCR, 0);
	ioasic_write(IO_REG_SCSI_DMA_P, vaddress << 3);

	/* prepare for next page */
	scsi_next_ptr = ((vaddress + PAGE_SIZE) & PAGE_MASK) << 3;
	ioasic_write(IO_REG_SCSI_DMA_BP, scsi_next_ptr);

	ioasic_ssr |= IO_SSR_SCSI_DMA_EN;
	fast_wmb();
	ioasic_write(IO_REG_SSR, ioasic_ssr);

	fast_iob();
	spin_unlock_irqrestore(&ioasic_ssr_lock, flags);
}

static void dma_ints_off(struct NCR_ESP *esp)
{
	disable_irq(dec_interrupt[DEC_IRQ_ASC_DMA]);
}

static void dma_ints_on(struct NCR_ESP *esp)
{
	enable_irq(dec_interrupt[DEC_IRQ_ASC_DMA]);
}

static int dma_irq_p(struct NCR_ESP *esp)
{
	return (esp->eregs->esp_status & ESP_STAT_INTR);
}

static int dma_ports_p(struct NCR_ESP *esp)
{
	/*
	 * FIXME: what's this good for?
	 */
	return 1;
}

static void dma_setup(struct NCR_ESP *esp, u32 addr, int count, int write)
{
	/*
	 * DMA_ST_WRITE means "move data from device to memory"
	 * so when (write) is true, it actually means READ!
	 */
	if (write)
		dma_init_read(esp, addr, count);
	else
		dma_init_write(esp, addr, count);
}

static void dma_mmu_get_scsi_one(struct NCR_ESP *esp, struct scsi_cmnd * sp)
{
	sp->SCp.ptr = (char *)virt_to_phys(sp->request_buffer);
}

static void dma_mmu_get_scsi_sgl(struct NCR_ESP *esp, struct scsi_cmnd * sp)
{
	int sz = sp->SCp.buffers_residual;
	struct scatterlist *sg = sp->SCp.buffer;

	while (sz >= 0) {
		sg[sz].dma_address = page_to_phys(sg[sz].page) + sg[sz].offset;
		sz--;
	}
	sp->SCp.ptr = (char *)(sp->SCp.buffer->dma_address);
}

static void dma_advance_sg(struct scsi_cmnd * sp)
{
	sp->SCp.ptr = (char *)(sp->SCp.buffer->dma_address);
}

static void pmaz_dma_drain(struct NCR_ESP *esp)
{
	memcpy(phys_to_virt(esp_virt_buffer),
	       (void *)CKSEG1ADDR(esp->slot + DEC_SCSI_SRAM +
				  ESP_TGT_DMA_SIZE),
	       scsi_current_length);
}

static void pmaz_dma_init_read(struct NCR_ESP *esp, u32 vaddress, int length)
{
	volatile u32 *dmareg =
		(volatile u32 *)CKSEG1ADDR(esp->slot + DEC_SCSI_DMAREG);

	if (length > ESP_TGT_DMA_SIZE)
		length = ESP_TGT_DMA_SIZE;

	*dmareg = TC_ESP_DMA_ADDR(ESP_TGT_DMA_SIZE);

	iob();

	esp_virt_buffer = vaddress;
	scsi_current_length = length;
}

static void pmaz_dma_init_write(struct NCR_ESP *esp, u32 vaddress, int length)
{
	volatile u32 *dmareg =
		(volatile u32 *)CKSEG1ADDR(esp->slot + DEC_SCSI_DMAREG);

	memcpy((void *)CKSEG1ADDR(esp->slot + DEC_SCSI_SRAM +
				  ESP_TGT_DMA_SIZE),
	       phys_to_virt(vaddress), length);

	wmb();
	*dmareg = TC_ESP_DMAR_WRITE | TC_ESP_DMA_ADDR(ESP_TGT_DMA_SIZE);

	iob();
}

static void pmaz_dma_ints_off(struct NCR_ESP *esp)
{
}

static void pmaz_dma_ints_on(struct NCR_ESP *esp)
{
}

static void pmaz_dma_setup(struct NCR_ESP *esp, u32 addr, int count, int write)
{
	/*
	 * DMA_ST_WRITE means "move data from device to memory"
	 * so when (write) is true, it actually means READ!
	 */
	if (write)
		pmaz_dma_init_read(esp, addr, count);
	else
		pmaz_dma_init_write(esp, addr, count);
}

static void pmaz_dma_mmu_get_scsi_one(struct NCR_ESP *esp, struct scsi_cmnd * sp)
{
	sp->SCp.ptr = (char *)virt_to_phys(sp->request_buffer);
}


#ifdef CONFIG_TC
static int __init dec_esp_tc_probe(struct device *dev);
static int __exit dec_esp_tc_remove(struct device *dev);

static const struct tc_device_id dec_esp_tc_table[] = {
        { "DEC     ", "PMAZ-AA " },
        { }
};
MODULE_DEVICE_TABLE(tc, dec_esp_tc_table);

static struct tc_driver dec_esp_tc_driver = {
        .id_table       = dec_esp_tc_table,
        .driver         = {
                .name   = "dec_esp",
                .bus    = &tc_bus_type,
                .probe  = dec_esp_tc_probe,
                .remove = __exit_p(dec_esp_tc_remove),
        },
};

static int __init dec_esp_tc_probe(struct device *dev)
{
	int status = dec_esp_probe(dev);
	if (!status)
		get_device(dev);
	return status;
}

static int __exit dec_esp_tc_remove(struct device *dev)
{
	put_device(dev);
	dec_esp_remove(dev);
	return 0;
}
#endif

static int __init dec_esp_init(void)
{
	int status;

	status = tc_register_driver(&dec_esp_tc_driver);
	if (!status)
		dec_esp_platform_probe();

	if (nesps) {
		pr_info("ESP: Total of %d ESP hosts found, "
			"%d actually in use.\n", nesps, esps_in_use);
		esps_running = esps_in_use;
	}

	return status;
}

static void __exit dec_esp_exit(void)
{
	dec_esp_platform_remove();
	tc_unregister_driver(&dec_esp_tc_driver);
}


module_init(dec_esp_init);
module_exit(dec_esp_exit);