PCI IO_BASE
Marco Schramel
Schramel.Linux at go.bartec.de
Thu Apr 28 00:59:52 EST 2005
Hi,
actually my system (2.4.25 on MPC8270 with PCI) runs fine and it will be tested. Thanks to all.
But one thing isn't really clear. The IO_BASE and memory windows for pci.
This is original taken from arch/ppc/plattforms/ads8260.h
/* window for a PCI master to access MPC8266 memory */
#define PCI_SLV_MEM_LOCAL 0x00000000 /* Local base */
#define PCI_SLV_MEM_BUS 0x00000000 /* PCI base */
/* window for the processor to access PCI memory with prefetching */
#define PCI_MSTR_MEM_LOCAL 0x80000000 /* Local base */
#define PCI_MSTR_MEM_BUS 0x80000000 /* PCI base */
#define PCI_MSTR_MEM_SIZE 0x20000000 /* 512MB */
/* window for the processor to access PCI memory without prefetching */
#define PCI_MSTR_MEMIO_LOCAL 0xA0000000 /* Local base */
#define PCI_MSTR_MEMIO_BUS 0xA0000000 /* PCI base */
#define PCI_MSTR_MEMIO_SIZE 0x20000000 /* 512MB */
/* window for the processor to access PCI I/O */
#define PCI_MSTR_IO_LOCAL 0xF4000000 /* Local base */
#define PCI_MSTR_IO_BUS 0x00000000 /* PCI base */
#define PCI_MSTR_IO_SIZE 0x04000000 /* 64MB */
#define _IO_BASE PCI_MSTR_IO_LOCAL
#define _ISA_MEM_BASE PCI_MSTR_MEMIO_LOCAL
#define PCI_DRAM_OFFSET PCI_SLV_MEM_BUS
#endif /* CONFIG_PCI */
These memory windows are not really clear to me. Which documentation can expand my theoretical background? Any comments are welcome.
If CONFIG_PCI is defined the io accesses will depend on the _IO_BASE (at example for ide accesses, now i know ;-)).
Why it depends on it ?
If i will adapt another chip with the standard io-accesses of /asm/io.h, which things i ve to know (offsets, windowsizes,etc..)?
Thanks for your comments.
Marco
--
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Marco Schramel
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