[SCSI] m68k: new mac_esp scsi driver

Replace the mac_esp driver with a new one based on the esp_scsi core.

For esp_scsi: add support for sync transfers for the PIO mode, add a new
esp_driver_ops method to get the maximum dma transfer size (like the old
NCR53C9x driver), and some cleanups.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

drivers/scsi/Kconfig

@@ -1677,6 +1677,16 @@ config MAC_SCSI
 	  SCSI-HOWTO, available from
 	  <http://www.tldp.org/docs.html#howto>.
 
+config SCSI_MAC_ESP
+	tristate "Macintosh NCR53c9[46] SCSI"
+	depends on MAC && SCSI
+	help
+	  This is the NCR 53c9x SCSI controller found on most of the 68040
+	  based Macintoshes.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called mac_esp.
+
 config MVME147_SCSI
 	bool "WD33C93 SCSI driver for MVME147"
 	depends on MVME147 && SCSI=y

drivers/scsi/Makefile

@@ -46,6 +46,7 @@ obj-$(CONFIG_MVME147_SCSI)	+= mvme147.o	wd33c93.o
 obj-$(CONFIG_SGIWD93_SCSI)	+= sgiwd93.o	wd33c93.o
 obj-$(CONFIG_ATARI_SCSI)	+= atari_scsi.o
 obj-$(CONFIG_MAC_SCSI)		+= mac_scsi.o
+obj-$(CONFIG_SCSI_MAC_ESP)	+= esp_scsi.o	mac_esp.o
 obj-$(CONFIG_SUN3_SCSI)		+= sun3_scsi.o  sun3_scsi_vme.o
 obj-$(CONFIG_MVME16x_SCSI)	+= 53c700.o	mvme16x_scsi.o
 obj-$(CONFIG_BVME6000_SCSI)	+= 53c700.o	bvme6000_scsi.o

drivers/scsi/esp_scsi.c

@@ -978,7 +978,7 @@ static int esp_check_spur_intr(struct esp *esp)
 			 */
 			if (!esp->ops->dma_error(esp)) {
 				printk(KERN_ERR PFX "esp%d: Spurious irq, "
-				       "sreg=%x.\n",
+				       "sreg=%02x.\n",
 				       esp->host->unique_id, esp->sreg);
 				return -1;
 			}
@@ -1447,6 +1447,9 @@ 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 rounded_up, one_clock;
 
@@ -1697,7 +1700,12 @@ static int esp_process_event(struct esp *esp)
 		else
 			ent->flags &= ~ESP_CMD_FLAG_WRITE;
 
-		dma_len = esp_dma_length_limit(esp, dma_addr, dma_len);
+		if (esp->ops->dma_length_limit)
+			dma_len = esp->ops->dma_length_limit(esp, dma_addr,
+							     dma_len);
+		else
+			dma_len = esp_dma_length_limit(esp, dma_addr, dma_len);
+
 		esp->data_dma_len = dma_len;
 
 		if (!dma_len) {
@@ -1761,7 +1769,6 @@ static int esp_process_event(struct esp *esp)
 		esp_advance_dma(esp, ent, cmd, bytes_sent);
 		esp_event(esp, ESP_EVENT_CHECK_PHASE);
 		goto again;
-		break;
 	}
 
 	case ESP_EVENT_STATUS: {
@@ -2235,7 +2242,7 @@ static void esp_bootup_reset(struct esp *esp)
 
 static void esp_set_clock_params(struct esp *esp)
 {
-	int fmhz;
+	int fhz;
 	u8 ccf;
 
 	/* This is getting messy but it has to be done correctly or else
@@ -2270,9 +2277,9 @@ static void esp_set_clock_params(struct esp *esp)
 	 *    This entails the smallest and largest sync period we could ever
 	 *    handle on this ESP.
 	 */
-	fmhz = esp->cfreq;
+	fhz = esp->cfreq;
 
-	ccf = ((fmhz / 1000000) + 4) / 5;
+	ccf = ((fhz / 1000000) + 4) / 5;
 	if (ccf == 1)
 		ccf = 2;
 
@@ -2281,16 +2288,16 @@ static void esp_set_clock_params(struct esp *esp)
 	 * been unable to find the clock-frequency PROM property.  All
 	 * other machines provide useful values it seems.
 	 */
-	if (fmhz <= 5000000 || ccf < 1 || ccf > 8) {
-		fmhz = 20000000;
+	if (fhz <= 5000000 || ccf < 1 || ccf > 8) {
+		fhz = 20000000;
 		ccf = 4;
 	}
 
 	esp->cfact = (ccf == 8 ? 0 : ccf);
-	esp->cfreq = fmhz;
-	esp->ccycle = ESP_MHZ_TO_CYCLE(fmhz);
+	esp->cfreq = fhz;
+	esp->ccycle = ESP_HZ_TO_CYCLE(fhz);
 	esp->ctick = ESP_TICK(ccf, esp->ccycle);
-	esp->neg_defp = ESP_NEG_DEFP(fmhz, ccf);
+	esp->neg_defp = ESP_NEG_DEFP(fhz, ccf);
 	esp->sync_defp = SYNC_DEFP_SLOW;
 }
 
@@ -2382,6 +2389,12 @@ 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) {

drivers/scsi/esp_scsi.h

@@ -224,7 +224,7 @@
 #define ESP_TIMEO_CONST       8192
 #define ESP_NEG_DEFP(mhz, cfact) \
         ((ESP_BUS_TIMEOUT * ((mhz) / 1000)) / (8192 * (cfact)))
-#define ESP_MHZ_TO_CYCLE(mhertz)  ((1000000000) / ((mhertz) / 1000))
+#define ESP_HZ_TO_CYCLE(hertz)  ((1000000000) / ((hertz) / 1000))
 #define ESP_TICK(ccf, cycle)  ((7682 * (ccf) * (cycle) / 1000))
 
 /* For slow to medium speed input clock rates we shoot for 5mb/s, but for high
@@ -368,6 +368,12 @@ struct esp_driver_ops {
 	 */
 	int (*irq_pending)(struct esp *esp);
 
+	/* Return the maximum allowable size of a DMA transfer for a
+	 * given buffer.
+	 */
+	u32 (*dma_length_limit)(struct esp *esp, u32 dma_addr,
+				u32 dma_len);
+
 	/* Reset the DMA engine entirely.  On return, ESP interrupts
 	 * should be enabled.  Often the interrupt enabling is
 	 * controlled in the DMA engine.
@@ -471,6 +477,7 @@ struct esp {
 #define ESP_FLAG_DOING_SLOWCMD	0x00000004
 #define ESP_FLAG_WIDE_CAPABLE	0x00000008
 #define ESP_FLAG_QUICKIRQ_CHECK	0x00000010
+#define ESP_FLAG_DISABLE_SYNC	0x00000020
 
 	u8			select_state;
 #define ESP_SELECT_NONE		0x00 /* Not selecting */