[PATCH] Revert "mpc85xx: ddr: Always start DDR RAM in Self Refresh mode"

[Joakim Tjernlund <Joakim.Tjernlund@infinera.com>]

On Thu, 2020-04-09 at 20:44 +0800, Biwen Li wrote:

This revert will bring back another bug, can you try finding out why it does work?
May there are some minor tweaks needed ?

       Jocke 
> 
> From: Biwen Li <biwen.li@nxp.com>
> 
> This reverts commit 2a5d5d27edfbdb0e02a7fcf05569f92c02ae44ee.
> After applied this patch, failed to boot to uboot(hang in ddr init)
> on P3041DS, P4080DS and so on.
> ---
>  drivers/ddr/fsl/mpc85xx_ddr_gen3.c | 13 +++++++------
>  1 file changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/ddr/fsl/mpc85xx_ddr_gen3.c b/drivers/ddr/fsl/mpc85xx_ddr_gen3.c
> index 952b296dd8..a9b085db8c 100644
> --- a/drivers/ddr/fsl/mpc85xx_ddr_gen3.c
> +++ b/drivers/ddr/fsl/mpc85xx_ddr_gen3.c
> @@ -370,8 +370,6 @@ step2:
>         debug("Setting DEBUG_3[21] to 0x%08x\n", in_be32(&ddr->debug[2]));
> 
>  #endif /* part 1 of the workaound */
> -       /* Always start in self-refresh, clear after MEM_EN */
> -       setbits_be32(&ddr->sdram_cfg_2, SDRAM_CFG2_FRC_SR);
> 
>         /*
>          * 500 painful micro-seconds must elapse between
> @@ -384,6 +382,8 @@ step2:
> 
>  #ifdef CONFIG_DEEP_SLEEP
>         if (is_warm_boot()) {
> +               /* enter self-refresh */
> +               setbits_be32(&ddr->sdram_cfg_2, SDRAM_CFG2_FRC_SR);
>                 /* do board specific memory setup */
>                 board_mem_sleep_setup();
>                 temp_sdram_cfg = (in_be32(&ddr->sdram_cfg) | SDRAM_CFG_BI);
> @@ -395,10 +395,6 @@ step2:
>         out_be32(&ddr->sdram_cfg, temp_sdram_cfg | SDRAM_CFG_MEM_EN);
>         asm volatile("sync;isync");
> 
> -       /* Exit self-refresh after DDR conf as some ddr memories can fail. */
> -       clrbits_be32(&ddr->sdram_cfg_2, SDRAM_CFG2_FRC_SR);
> -       asm volatile("sync;isync");
> -
>         total_gb_size_per_controller = 0;
>         for (i = 0; i < CONFIG_CHIP_SELECTS_PER_CTRL; i++) {
>                 if (!(regs->cs[i].config & 0x80000000))
> @@ -548,4 +544,9 @@ step2:
>                 clrbits_be32(&ddr->sdram_cfg, 0x2);
>         }
>  #endif /* CONFIG_SYS_FSL_ERRATUM_DDR111_DDR134 */
> +#ifdef CONFIG_DEEP_SLEEP
> +       if (is_warm_boot())
> +               /* exit self-refresh */
> +               clrbits_be32(&ddr->sdram_cfg_2, SDRAM_CFG2_FRC_SR);
> +#endif
>  }
> --
> 2.17.1
>