bcm63xx_enet: split DMA channel register accesses

The current bcm63xx_enet driver always uses bcmenet_shared_base whenever
it needs to access DMA channel configuration space or access the DMA
channel state RAM. Split these register in 3 parts to be more accurate:

- global DMA configuration
- per DMA channel configuration space
- per DMA channel state RAM space

This is preliminary to support new chips where the global DMA
configuration remains the same, but there is a varying number of DMA
channels located at a different memory offset.

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/mips/bcm63xx/dev-enet.c b/arch/mips/bcm63xx/dev-enet.c
index 39c2336..df5bf66 100644
--- a/arch/mips/bcm63xx/dev-enet.c
+++ b/arch/mips/bcm63xx/dev-enet.c
@@ -19,6 +19,16 @@
 		.end		= -1, /* filled at runtime */
 		.flags		= IORESOURCE_MEM,
 	},
+	{
+		.start		= -1, /* filled at runtime */
+		.end		= -1, /* filled at runtime */
+		.flags		= IORESOURCE_MEM,
+	},
+	{
+		.start		= -1, /* filled at runtime */
+		.end		= -1, /* filled at runtime */
+		.flags		= IORESOURCE_MEM,
+	},
 };
 
 static struct platform_device bcm63xx_enet_shared_device = {
@@ -110,10 +120,15 @@
 	if (!shared_device_registered) {
 		shared_res[0].start = bcm63xx_regset_address(RSET_ENETDMA);
 		shared_res[0].end = shared_res[0].start;
-		if (BCMCPU_IS_6338())
-			shared_res[0].end += (RSET_ENETDMA_SIZE / 2)  - 1;
-		else
-			shared_res[0].end += (RSET_ENETDMA_SIZE)  - 1;
+		shared_res[0].end += (RSET_ENETDMA_SIZE)  - 1;
+
+		shared_res[1].start = bcm63xx_regset_address(RSET_ENETDMAC);
+		shared_res[1].end = shared_res[1].start;
+		shared_res[1].end += RSET_ENETDMAC_SIZE(16)  - 1;
+
+		shared_res[2].start = bcm63xx_regset_address(RSET_ENETDMAS);
+		shared_res[2].end = shared_res[2].start;
+		shared_res[2].end += RSET_ENETDMAS_SIZE(16)  - 1;
 
 		ret = platform_device_register(&bcm63xx_enet_shared_device);
 		if (ret)
diff --git a/arch/mips/include/asm/mach-bcm63xx/bcm63xx_cpu.h b/arch/mips/include/asm/mach-bcm63xx/bcm63xx_cpu.h
index 3362289..9981f4f 100644
--- a/arch/mips/include/asm/mach-bcm63xx/bcm63xx_cpu.h
+++ b/arch/mips/include/asm/mach-bcm63xx/bcm63xx_cpu.h
@@ -173,7 +173,9 @@
 #define BCM_6358_RSET_SPI_SIZE		1804
 #define BCM_6368_RSET_SPI_SIZE		1804
 #define RSET_ENET_SIZE			2048
-#define RSET_ENETDMA_SIZE		2048
+#define RSET_ENETDMA_SIZE		256
+#define RSET_ENETDMAC_SIZE(chans)	(16 * (chans))
+#define RSET_ENETDMAS_SIZE(chans)	(16 * (chans))
 #define RSET_ENETSW_SIZE		65536
 #define RSET_UART_SIZE			24
 #define RSET_UDC_SIZE			256