The criteria of the AMCC SDRAM Controller DDR autocalibration
U-Boot code is to pick the largest passing write/read/compare
window that also has the smallest SDRAM_RDCC.[RDSS] Read Sample
Cycle Select value.
On some Kilauea boards the DDR autocalibration algorithm can
find a large passing write/read/compare window with a small
SDRAM_RDCC.[RDSS] aggressive value of Read Sample Cycle Select
value "T1 Sample".
This SDRAM_RDCC.[RDSS] Read Sample Cycle Select value of
"T1 Sample" proves to be to aggressive when later on U-Boot
relocates into DDR memory and executes.
The memory traces on the Kilauea board are short so on some
Kilauea boards the SDRAM_RDCC.[RDSS] Read Sample Cycle Select
value of "T1 Sample" shows up as a potentially valid value for
the DDR autocalibratiion algorithm.
The fix is to define a weak default function which provides
the minimum SDRAM_RDCC.[RDSS] Read Sample Cycle Select value
to accept for DDR autocalibration. The default will be the
"T2 Sample" value. A board developer who has a well defined
board and chooses to be more aggressive can always provide
their own board specific string function with the more
aggressive "T1 Sample" value or stick with the default
minimum SDRAM_RDCC.[RDSS] value of "T2".
Also put in a autocalibration loop fix for case where current
write/read/compare passing window size is the same as a prior
window size, then in this case choose the write/read/compare
result that has the associated smallest RDCC T-Sample value.
Signed-off-by: Adam Graham <agraham@amcc.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Set the MQ Read Passing & MCIF Cycle limits to the recommended by AMCC
values. This fixes the occasional 440SPe hard locking issues when the 440SPe's
dedicated DMA engines are used (e.g. by the h/w accelerated RAID driver).
Previously the appropriate initialization had been made in Linux, by the
ppc440spe ADMA driver, which is wrong because modifying the MQ configuration
registers after normal operation has begun is not supported and could
have unpredictable results.
Comment from Stefan: This patch doesn't change the resulting value of the
MQ registers. It explicitly sets/clears all bits to the desired state which
better documents the resulting register value instead of relying on pre-set
default values.
Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Stefan Roese <sr@denx.de>
PPC405EX and PPC460EX/GT/SX
- Read pipeline depth set to 4 for PPC440SP/SPE, PPC405EX, PPC460EX/GT/SX
processors
- Moved PLB4 Arbiter register definitions to ppc4xx.h since it is shared
across processors (405 and 440/460)
- Optimize Memory Queue settings for PPC440SP/SPE and PPC460EX/GT/SX
processors
- Add register bit definitions for Memory Queue Configuration registers
Signed-off-by: Prodyut Hazarika <phazarika@amcc.com>
Signed-off-by: Stefan Roese <sr@denx.de>
This patch completes the preprocessor mneomics for the IBM DDR2 SDRAM
controller registers (MODT and INITPLR) used by the
PowerPC405EX(r). The MMODE and MEMODE registers are unified with their
peer values used for the INITPLR MR and EMR registers,
respectively. Finally, a spelling typo is correct (MANUEL to MANUAL).
With these mnemonics in place, the CFG_SDRAM0_* magic numbers for
Kilauea are replaced by equivalent mnemonics to make it easier to
compare and contrast other 405EX(r)-based boards (e.g. during board
bring-up).
Finally, unified the SDRAM controller register dump routine such that
it can be used across all processor variants that utilize the IBM DDR2
SDRAM controller core. It produces output of the form:
PPC4xx IBM DDR2 Register Dump:
...
SDRAM_MB0CF[40] = 0x00006701
...
which is '<mnemonic>[<DCR #>] = <value>'. The DCR number is included
since it is not uncommon that the DCR values in header files get mixed
up and it helps to validate, at a glance, they match what is printed
in the user manual.
Tested on:
AMCC Kilauea/Haleakala:
- NFS Linux Boot: PASSED
- NAND Linux Boot: PASSED
Signed-off-by: Grant Erickson <gerickson@nuovations.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Add additional DDR2 SDRAM memory controller DCR mneomnics, condition
revision ID DCR based on 405EX, and add field mnemonics for bus error
status and ECC error status registers.
Signed-off-by: Grant Erickson <gerickson@nuovations.com>
Signed-off-by: Stefan Roese <sr@denx.de>
While the PowerPC 405EX(r) shares in common the AMCC/IBM DDR2 SDRAM
controller core also used in the 440SP, 440SPe, 460EX, and 460GT, in
the 405EX(r), SDRAM_MCSTAT has a different DCR value.
Its present value on the 405EX(r) causes a read back of 0xFFFFFFFF
which causes SDRAM initialization to periodically fail since it can
prematurely indicate SDRAM ready status.
Signed-off-by: Grant Erickson <gerickson@nuovations.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Newer PPC's like 440SPe, 460EX/GT can be equipped with more than 2GB of SDRAM.
To support such configurations, we "only" map the first 2GB via the TLB's. We
need some free virtual address space for the remaining peripherals like, SoC
devices, FLASH etc.
Note that ECC is currently not supported on configurations with more than 2GB
SDRAM. This is because we only map the first 2GB on such systems, and therefore
the ECC parity byte of the remaining area can't be written.
Signed-off-by: Stefan Roese <sr@denx.de>
This patch now adds a new header file (asm-ppc/ppc4xx-sdram.h) for all
ppc4xx related SDRAM/DDR/DDR2 controller defines.
Signed-off-by: Stefan Roese <sr@denx.de>
