Re: Busmaster DMA broken in 2.4.18 on Alpha

[Ivan Kokshaysky]

On Mon, Mar 11, 2002 at 12:45:11PM +0100, Kurt Garloff wrote:
> Unfortunately, your ISA card does not seem to be able to address 32 bits.
> (I guess no non-on-chip ISA adapter will.)

No, the ability to address 32 bits is property of an ISA bridge, not
of any particular ISA card or device. Most alphas do have 32-bit ISA DMA.

For that particular driver the following hack should work.
However, ideally we should have ISA_DMA_MASK in asm/dma.h defined
for all architectures...

Ivan.

--- linux/drivers/net/tokenring/tms380tr.h.orig	Fri May 25 20:58:07 2001
+++ linux/drivers/net/tokenring/tms380tr.h	Mon Mar 11 15:52:06 2002
@@ -462,7 +462,12 @@ typedef struct {
 				  */
 
 /* XXX is there some better way to do this? */
+#if defined(__alpha__)
+#define ISA_MAX_ADDRESS	(MAX_DMA_ADDRESS - IDENT_ADDR - 1 < 0xffffffff ? \
+			 MAX_DMA_ADDRESS - IDENT_ADDR - 1 : 0xffffffff)
+#else
 #define ISA_MAX_ADDRESS 	0x00ffffff
+#endif
 #define PCI_MAX_ADDRESS		0xffffffff
 
 #pragma pack(1)