Commit 0a07232f authored by Krzysztof Hałasa's avatar Krzysztof Hałasa

IXP4xx: workaround for PCI prefetch problems near 64 MB boundary.

Map unused registers at the end of DMA region at 64 MB to allow PCI masters
to cross the boundary when prefetching data from SDRAM.
Signed-off-by: default avatarKrzysztof Hałasa <khc@pm.waw.pl>
parent fec6c6fe
...@@ -43,6 +43,7 @@ ...@@ -43,6 +43,7 @@
#define SZ_8M 0x00800000 #define SZ_8M 0x00800000
#define SZ_16M 0x01000000 #define SZ_16M 0x01000000
#define SZ_32M 0x02000000 #define SZ_32M 0x02000000
#define SZ_48M 0x03000000
#define SZ_64M 0x04000000 #define SZ_64M 0x04000000
#define SZ_128M 0x08000000 #define SZ_128M 0x08000000
#define SZ_256M 0x10000000 #define SZ_256M 0x10000000
......
...@@ -411,15 +411,16 @@ void __init ixp4xx_pci_preinit(void) ...@@ -411,15 +411,16 @@ void __init ixp4xx_pci_preinit(void)
* We configure the PCI inbound memory windows to be * We configure the PCI inbound memory windows to be
* 1:1 mapped to SDRAM * 1:1 mapped to SDRAM
*/ */
local_write_config(PCI_BASE_ADDRESS_0, 4, PHYS_OFFSET + 0x00000000); local_write_config(PCI_BASE_ADDRESS_0, 4, PHYS_OFFSET);
local_write_config(PCI_BASE_ADDRESS_1, 4, PHYS_OFFSET + 0x01000000); local_write_config(PCI_BASE_ADDRESS_1, 4, PHYS_OFFSET + SZ_16M);
local_write_config(PCI_BASE_ADDRESS_2, 4, PHYS_OFFSET + 0x02000000); local_write_config(PCI_BASE_ADDRESS_2, 4, PHYS_OFFSET + SZ_32M);
local_write_config(PCI_BASE_ADDRESS_3, 4, PHYS_OFFSET + 0x03000000); local_write_config(PCI_BASE_ADDRESS_3, 4, PHYS_OFFSET + SZ_48M);
/* /*
* Enable CSR window at 0xff000000. * Enable CSR window at 64 MiB to allow PCI masters
* to continue prefetching past 64 MiB boundary.
*/ */
local_write_config(PCI_BASE_ADDRESS_4, 4, 0xff000008); local_write_config(PCI_BASE_ADDRESS_4, 4, PHYS_OFFSET + SZ_64M);
/* /*
* Enable the IO window to be way up high, at 0xfffffc00 * Enable the IO window to be way up high, at 0xfffffc00
......
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