Quoting Corey Osgood corey.osgood@gmail.com:
On Tue, 2008-02-26 at 16:19 -0500, joe@smittys.pointclark.net wrote:
+static void do_ram_command(const struct mem_controller *ctrl, uint32_t command, uint32_t addr_offset) +{
<snip> + + /* Read from (DIMM start address + addr_offset). */ + read32(0 + addr_offset); //first offset is always 0 +}
This isn't ready for multiple dimms yet. See the cn700 patch I recently sent (but haven't committed yet, I think it was acked).
Oh you mean this? What do I need to do to adapt it for the i82830?
- /* NOTE: Dual-sided ready */ read32(0 + addr_offset);
- for(i = 0; i < (ARRAY_SIZE(ctrl->channel0) * 2); i++) {
reg8 = pci_read_config8(ctrl->d0f3, 0x40 + i);- if(reg8) read32((reg8 << 26) + addr_offset);
- }
This reads from register 0x40 + i, where 0x40 is the top of the first dimm, and i counts to the max number of dimms.
Why read this from a register?? Why not just use (i = 0; i < DIMM_SOCKETS; i++)
Reg 0x40 contains bits 33:26 of the top address, hence the << 26. So you'd need to adjust both of these to fit the i830's DRB mechanism. If the i830 uses an ugly format like the i810 does, then it may be easier to store the size in scratch registers somewhere after it's calculated, and then use those values instead. Sorry I can't get more specific, I've got to head out to my next service call.
The DRB i830 is not ugly it is very simple, simple, simple. So simple that it just calculates the memory size in ticks of 32 per side * the next side up to 4 sides. Like this:
Example: 128MB SINGLE sided so-dimm in slot 1 128MB DOUBLE sided so-dimm in slot 2
There are 4 DRB registers(actually 6 but but only 4 that are usable - Intel design glitch), 1 for each side. So in this example they would look like this:
DRB1 = 0x04 DRB2 = 0x04 DRB3 = 0x06 DRB4 = 0x08
So if we needed to convert this we would do something like this (DRB * 32) * 1024 correct? But if we just need to calculate the end of so-dimm #1 and the start of so-dimm #2 the only important register would be DRB2 (side 2 of so-dimm #1) and DRB3(side 1 of so-dimm #2), correct?
Thanks - Joe