On 02/04/2018 05:40 AM, Simon Glass wrote:
Hi York,
On 24 January 2018 at 12:04, York Sun york.sun@nxp.com wrote:
For DDR4, command/address delay in mode registers and parity latency in timing config register are only needed for UDIMMs, but not RDIMMs. Add additional register rcw_3 for DDR4 RDIMM. Fix mirrored bit for dual rank RDIMMs. Set sdram_cfg_3[DIS_MRS_PAR] for RDIMMs. Use hexadecimal format for printing RCW (register control word) registers.
Signed-off-by: York Sun york.sun@nxp.com
Changes in v3: None Changes in v2: None
drivers/ddr/fsl/ctrl_regs.c | 32 +++++++++++++++++++++++++------- drivers/ddr/fsl/ddr4_dimm_params.c | 2 ++ drivers/ddr/fsl/interactive.c | 9 +++++++-- include/fsl_ddr_sdram.h | 1 + 4 files changed, 35 insertions(+), 9 deletions(-)
What do you think about moving this into drivers/ram (separate from this patch)? Do you think it could use the uclass?
Simon,
Moving to drivers/ram is not a problem. My concern is it is worth the effort. Legacy PowerPC-based SoCs are still alive but I don't see any new products coming. ARM-based SoCs will move to ATF (or alike) boots first model. Once ATF boots first, U-Boot will no longer need this driver (PowerPC SoCs still use it though). Let's discuss this again a few months later when I may have a better vision.
York