[U-Boot-Users] 85xx CDS question
Hi all, I pulled u-boot from git today since the merge window is now cleared. I'm gearing u-boot up for my custom 8548 board that'll be ready this week. My question is about PCI2 Memory in the CDS example - I don't see an entry here:
* 0x0000_0000 0x7fff_ffff DDR 2G * 0x8000_0000 0x9fff_ffff PCI1 MEM 512M * 0xa000_0000 0xbfff_ffff PCIe MEM 512M * 0xc000_0000 0xdfff_ffff RapidIO 512M * 0xe000_0000 0xe000_ffff CCSR 1M * 0xe200_0000 0xe10f_ffff PCI1 IO 1M * 0xe280_0000 0xe20f_ffff PCI2 IO 1M * 0xe300_0000 0xe30f_ffff PCIe IO 1M * 0xf000_0000 0xf3ff_ffff SDRAM 64M * 0xf800_0000 0xf80f_ffff NVRAM/CADMUS (*) 1M * 0xff00_0000 0xff7f_ffff FLASH (2nd bank) 8M * 0xff80_0000 0xffff_ffff FLASH (boot bank) 8M
My board is similair except we don't have RapidIO, SDRAM or CADMUS. Without RapidIO, we have PCIE as 8x speed if that matters.
Looking at the manual, Table 16-3 says "PCI/X Controller 2 Memory-Mapped Registers—Block Base Address 0x0_9000" . Is the above entry for both PCI1 and PCI2 ?
Thanks! Robert
The 8548 CDS doesn't have PCI2 exposed. PCI1 is routed through the PCI edge connector. PCIe is routed through the slot on the opposite side of the card. There's no room for PCI2, so it's orphaned. On the 8555, PCI2 is routed to where the PCIe slot is on 8548.
Suffice it to say, if you want to use PCI2 on 8548, you'll need to devise your own memory map. The PCI2_IO is probably left over from porting the CDS from the 8555/8541 to the 8548. I will look into cleaning up the comments in that file to reflect reality. :)
Andy
On 8/20/07, Andy Fleming afleming@gmail.com wrote:
The 8548 CDS doesn't have PCI2 exposed. PCI1 is routed through the PCI edge connector. PCIe is routed through the slot on the opposite side of the card. There's no room for PCI2, so it's orphaned. On the 8555, PCI2 is routed to where the PCIe slot is on 8548.
Suffice it to say, if you want to use PCI2 on 8548, you'll need to devise your own memory map. The PCI2_IO is probably left over from porting the CDS from the 8555/8541 to the 8548. I will look into cleaning up the comments in that file to reflect reality. :)
Andy
Thanks Andy, as I don't have the mpc8548cds on hand. I can't find an 85xx example that has both PCIe and PCI2. What's confusing me is that I'm seeing this mapping on the mpc8541cds:
* 0xa000_0000 0xbfff_ffff PCI2 MEM 512M
And in mpc8548cds:
* 0xa000_0000 0xbfff_ffff PCIe MEM 512M
Its legal on 85xx to define the same memory area for either PCI2 or PCIe ? If so, here's my idea. I don't have RapidIO - can I do use the memory map that mpc8548cds uses:
* 0xc000_0000 0xdfff_ffff RapidIO 512M
For my board as?
* 0xc000_0000 0xdfff_ffff PCI2 MEM 512M
Thanks for the help! Robert
On 8/20/07, robert lazarski robertlazarski@gmail.com wrote:
On 8/20/07, Andy Fleming afleming@gmail.com wrote:
Thanks Andy, as I don't have the mpc8548cds on hand. I can't find an 85xx example that has both PCIe and PCI2. What's confusing me is that I'm seeing this mapping on the mpc8541cds:
- 0xa000_0000 0xbfff_ffff PCI2 MEM 512M
And in mpc8548cds:
- 0xa000_0000 0xbfff_ffff PCIe MEM 512M
Well, keep in mind those are the comments. You might want to look at the config files to confirm the actual mappings.
Its legal on 85xx to define the same memory area for either PCI2 or PCIe ? If so, here's my idea. I don't have RapidIO - can I do use the memory map that mpc8548cds uses:
- 0xc000_0000 0xdfff_ffff RapidIO 512M
For my board as?
- 0xc000_0000 0xdfff_ffff PCI2 MEM 512M
You can do whatever you want. :) You just need to change the config file, and make sure that you have the appropriate entries in your init.S file to set the LAWs and TLBs appropriately.
Andy
participants (2)
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Andy Fleming -
robert lazarski