Change the DBDMA API to allow DBDMA registers in a subregion of a resource. This is necessary to allow future support of DMA for the various Apple on-board ATA controllers.

MFC after:	1 week

4 files changed, 14 insertions, 11 deletions

diff --git a/sys/dev/bm/if_bm.c b/sys/dev/bm/if_bm.c
index 9f881e6..6c3789c 100644
--- a/sys/dev/bm/if_bm.c
+++ b/sys/dev/bm/if_bm.c
@@ -488,9 +488,9 @@ bm_attach(device_t dev)
 		return (ENXIO);
 	}
 
-	error = dbdma_allocate_channel(sc->sc_txdmar, bus_get_dma_tag(dev),
+	error = dbdma_allocate_channel(sc->sc_txdmar, 0, bus_get_dma_tag(dev),
 	    BM_MAX_DMA_COMMANDS, &sc->sc_txdma);
-	error += dbdma_allocate_channel(sc->sc_rxdmar, bus_get_dma_tag(dev),
+	error += dbdma_allocate_channel(sc->sc_rxdmar, 0, bus_get_dma_tag(dev),
 	    BM_MAX_DMA_COMMANDS, &sc->sc_rxdma);
 
 	if (error) {
diff --git a/sys/powerpc/include/dbdma.h b/sys/powerpc/include/dbdma.h
index 0f035d4..becfbc8 100644
--- a/sys/powerpc/include/dbdma.h
+++ b/sys/powerpc/include/dbdma.h
@@ -78,7 +78,7 @@ typedef struct dbdma_command dbdma_command_t;
 struct dbdma_channel;
 typedef struct dbdma_channel dbdma_channel_t;
 
-int dbdma_allocate_channel(struct resource *dbdma_regs,
+int dbdma_allocate_channel(struct resource *dbdma_regs, u_int offset,
     bus_dma_tag_t parent_dma, int slots, dbdma_channel_t **chan);
 
 int dbdma_resize_channel(dbdma_channel_t *chan, int newslots);
diff --git a/sys/powerpc/powermac/dbdma.c b/sys/powerpc/powermac/dbdma.c
index 71bf417..edae6e2 100644
--- a/sys/powerpc/powermac/dbdma.c
+++ b/sys/powerpc/powermac/dbdma.c
@@ -56,8 +56,8 @@ dbdma_phys_callback(void *chan, bus_dma_segment_t *segs, int nsegs, int error)
 }
 
 int
-dbdma_allocate_channel(struct resource *dbdma_regs, bus_dma_tag_t parent_dma,
-    int slots, dbdma_channel_t **chan)
+dbdma_allocate_channel(struct resource *dbdma_regs, u_int offset,
+    bus_dma_tag_t parent_dma, int slots, dbdma_channel_t **chan)
 {
 	int error = 0;
 	dbdma_channel_t *channel;
@@ -65,8 +65,8 @@ dbdma_allocate_channel(struct resource *dbdma_regs, bus_dma_tag_t parent_dma,
 	channel = *chan = malloc(sizeof(struct dbdma_channel), M_DBDMA, 
 	    M_WAITOK | M_ZERO);
 
-	channel->sc_bt = rman_get_bustag(dbdma_regs);
-	channel->sc_bh = rman_get_bushandle(dbdma_regs);
+	channel->sc_regs = dbdma_regs;
+	channel->sc_off = offset;
 	dbdma_stop(channel);
 
 	channel->sc_slots_pa = 0;
@@ -82,6 +82,8 @@ dbdma_allocate_channel(struct resource *dbdma_regs, bus_dma_tag_t parent_dma,
 	error = bus_dmamap_load(channel->sc_dmatag, channel->sc_dmamap,
 	    channel->sc_slots, PAGE_SIZE, dbdma_phys_callback, channel, 0);
 
+	dbdma_write_reg(channel, CHAN_CMDPTR_HI, 0);
+
 	channel->sc_nslots = slots;
 
 	return (error);
@@ -320,12 +322,12 @@ static uint32_t
 dbdma_read_reg(dbdma_channel_t *chan, u_int offset)
 {
 
-	return (bus_space_read_4(chan->sc_bt, chan->sc_bh, offset));
+	return (bus_read_4(chan->sc_regs, chan->sc_off + offset));
 }
 
 static void
 dbdma_write_reg(dbdma_channel_t *chan, u_int offset, uint32_t val)
 {
 
-	bus_space_write_4(chan->sc_bt, chan->sc_bh, offset, val);
+	bus_write_4(chan->sc_regs, chan->sc_off + offset, val);
 }
diff --git a/sys/powerpc/powermac/dbdmavar.h b/sys/powerpc/powermac/dbdmavar.h
index c69da13..88c3185 100644
--- a/sys/powerpc/powermac/dbdmavar.h
+++ b/sys/powerpc/powermac/dbdmavar.h
@@ -51,8 +51,8 @@ struct dbdma_command {
 };
 
 struct dbdma_channel {
-	bus_space_tag_t		sc_bt;
-	bus_space_handle_t	sc_bh;
+	struct resource 	*sc_regs;
+	u_int			sc_off;
 
 	struct dbdma_command	*sc_slots;
 	int			sc_nslots;
@@ -78,6 +78,7 @@ struct dbdma_channel {
 
 #define CHAN_CONTROL_REG	0x00
 #define	CHAN_STATUS_REG		0x04
+#define CHAN_CMDPTR_HI		0x08
 #define CHAN_CMDPTR		0x0C
 #define	CHAN_INTR_SELECT	0x10
 #define CHAN_BRANCH_SELECT	0x14