sh: pci: Disable MWI and make pci_dma_burst_advice() a bit more accurate.
None of the SH PCI controllers support MWI, it is always treated as a
direct memory write, so simply disable it outright. In the case of the
PCI cache line size, consult that for the pci_dma_burst_advice()
strategy, and switch over to PCI_DMA_BURST_MULTIPLE, as PPC64.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/include/asm/pci.h b/arch/sh/include/asm/pci.h
index 5b2e0fc..ae0da6f 100644
--- a/arch/sh/include/asm/pci.h
+++ b/arch/sh/include/asm/pci.h
@@ -89,12 +89,28 @@
#endif
#ifdef CONFIG_PCI
+/*
+ * None of the SH PCI controllers support MWI, it is always treated as a
+ * direct memory write.
+ */
+#define PCI_DISABLE_MWI
+
static inline void pci_dma_burst_advice(struct pci_dev *pdev,
enum pci_dma_burst_strategy *strat,
unsigned long *strategy_parameter)
{
- *strat = PCI_DMA_BURST_INFINITY;
- *strategy_parameter = ~0UL;
+ unsigned long cacheline_size;
+ u8 byte;
+
+ pci_read_config_byte(pdev, PCI_CACHE_LINE_SIZE, &byte);
+
+ if (byte == 0)
+ cacheline_size = L1_CACHE_BYTES;
+ else
+ cacheline_size = byte << 2;
+
+ *strat = PCI_DMA_BURST_MULTIPLE;
+ *strategy_parameter = cacheline_size;
}
#endif