Commit 02507a80 authored by Finn Thain's avatar Finn Thain Committed by James Bottomley
Browse files

[SCSI] mac_esp: fix PIO mode, take 2 



The mac_esp PIO algorithm no longer works in 2.6.31 and crashes my Centris
660av. So here's a better one.

Also, force async with esp_set_offset() rather than esp_slave_configure().

One of the SCSI drives I tested still doesn't like the PIO mode and fails
with "esp: esp0: Reconnect IRQ2 timeout" (the same drive works fine in
PDMA mode).

This failure happens when esp_reconnect_with_tag() tries to read in two
tag bytes but the chip only provides one (0x20). I don't know what causes
this. I decided not to waste any more time trying to fix it because the
best solution is to rip out the PIO mode altogether and use the DMA
engine.

Signed-off-by: default avatarFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@suse.de>
parent f2818663

drivers/scsi/esp_scsi.c

+4 −10
Original line number Diff line number Diff line
@@ -1449,9 +1449,6 @@ static void esp_msgin_sdtr(struct esp *esp, struct esp_target_data *tp) 
	if (offset > 15)

		goto do_reject;



	if (esp->flags & ESP_FLAG_DISABLE_SYNC)

		offset = 0;



	if (offset) {

		int one_clock;
@@ -2405,12 +2402,6 @@ static int esp_slave_configure(struct scsi_device *dev) 
	struct esp_target_data *tp = &esp->target[dev->id];

	int goal_tags, queue_depth;



	if (esp->flags & ESP_FLAG_DISABLE_SYNC) {

		/* Bypass async domain validation */

		dev->ppr  = 0;

		dev->sdtr = 0;

	}



	goal_tags = 0;



	if (dev->tagged_supported) {
@@ -2660,6 +2651,9 @@ static void esp_set_offset(struct scsi_target *target, int offset) 
	struct esp *esp = shost_priv(host);

	struct esp_target_data *tp = &esp->target[target->id];



	if (esp->flags & ESP_FLAG_DISABLE_SYNC)

		tp->nego_goal_offset = 0;

	else

		tp->nego_goal_offset = offset;

	tp->flags |= ESP_TGT_CHECK_NEGO;

}

drivers/scsi/mac_esp.c

+49 −46
Original line number Diff line number Diff line
@@ -22,7 +22,6 @@ 


#include <asm/irq.h>

#include <asm/dma.h>



#include <asm/macints.h>

#include <asm/macintosh.h>
@@ -279,24 +278,27 @@ static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count, 
 * Programmed IO routines follow.

 */



static inline int mac_esp_wait_for_fifo(struct esp *esp)

static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp)

{

	int i = 500000;



	do {

		if (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES)

			return 0;

		unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;



		if (fbytes)

			return fbytes;



		udelay(2);

	} while (--i);



	printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n",

	       esp_read8(ESP_STATUS));

	return 1;

	return 0;

}



static inline int mac_esp_wait_for_intr(struct esp *esp)

{

	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);

	int i = 500000;



	do {
@@ -308,6 +310,7 @@ static inline int mac_esp_wait_for_intr(struct esp *esp) 
	} while (--i);



	printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg);

	mep->error = 1;

	return 1;

}
@@ -347,11 +350,10 @@ static inline int mac_esp_wait_for_intr(struct esp *esp) 
static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,

				 u32 dma_count, int write, u8 cmd)

{

	unsigned long flags;

	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);

	u8 *fifo = esp->regs + ESP_FDATA * 16;



	local_irq_save(flags);

	disable_irq(esp->host->irq);



	cmd &= ~ESP_CMD_DMA;

	mep->error = 0;
@@ -359,62 +361,63 @@ static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count, 
	if (write) {

		scsi_esp_cmd(esp, cmd);



		if (!mac_esp_wait_for_intr(esp)) {

			if (mac_esp_wait_for_fifo(esp))

				esp_count = 0;

		} else {

			esp_count = 0;

		}

	} else {

		scsi_esp_cmd(esp, ESP_CMD_FLUSH);



		if (esp_count >= MAC_ESP_FIFO_SIZE)

			MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);

		else

			MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count);



		scsi_esp_cmd(esp, cmd);

	}



	while (esp_count) {

		while (1) {

			unsigned int n;



		if (mac_esp_wait_for_intr(esp)) {

			mep->error = 1;

			break;

		}



		if (esp->sreg & ESP_STAT_SPAM) {

			printk(KERN_ERR PFX "gross error\n");

			mep->error = 1;

			n = mac_esp_wait_for_fifo(esp);

			if (!n)

				break;

		}



		n = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;



		if (write) {

			if (n > esp_count)

				n = esp_count;

			esp_count -= n;



			MAC_ESP_PIO_LOOP("%2@,%0@+", n);



			if ((esp->sreg & ESP_STAT_PMASK) == ESP_STATP)

			if (!esp_count)

				break;



			if (mac_esp_wait_for_intr(esp))

				break;



			if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) &&

			    ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP))

				break;



			if (esp_count) {

			esp->ireg = esp_read8(ESP_INTRPT);

				if (esp->ireg & ESP_INTR_DC)

			if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=

			    ESP_INTR_BSERV)

				break;



			scsi_esp_cmd(esp, ESP_CMD_TI);

		}

	} else {

		scsi_esp_cmd(esp, ESP_CMD_FLUSH);



		if (esp_count >= MAC_ESP_FIFO_SIZE)

			MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);

		else

			MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count);



		scsi_esp_cmd(esp, cmd);



		while (esp_count) {

			unsigned int n;



			if (mac_esp_wait_for_intr(esp))

				break;



			if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) &&

			    ((esp->sreg & ESP_STAT_PMASK) != ESP_MOP))

				break;



			esp->ireg = esp_read8(ESP_INTRPT);

			if (esp->ireg & ESP_INTR_DC)

			if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=

			    ESP_INTR_BSERV)

				break;



			n = MAC_ESP_FIFO_SIZE - n;

			n = MAC_ESP_FIFO_SIZE -

			    (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);

			if (n > esp_count)

				n = esp_count;
@@ -429,7 +432,7 @@ static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count, 
		}

	}



	local_irq_restore(flags);

	enable_irq(esp->host->irq);

}



static int mac_esp_irq_pending(struct esp *esp)

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