[Skiboot] [PATCH 59/61] xive2: Add NCU_SPEC_BAR to stop engine for restore

[Cédric Le Goater]

On 7/19/21 3:20 PM, Vasant Hegde wrote:
> From: Vaidyanathan Srinivasan <svaidy at linux.ibm.com>
> 
> P10 Stop engines have apis similar to P9 to set xscom restores
> after wakeup from deep-sleep states.
> 
> This xscom restore will be used to support STOP11 on P10.
> 
> Signed-off-by: Vaidyanathan Srinivasan <svaidy at linux.ibm.com>
> Signed-off-by: Pratik Rajesh Sampat <psampat at linux.ibm.com>
> Signed-off-by: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
> ---
>  hw/xive2.c | 31 ++++++++++++++++++++++++++-----
>  1 file changed, 26 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/xive2.c b/hw/xive2.c
> index f559b0f9a..d2fc2ad69 100644
> --- a/hw/xive2.c
> +++ b/hw/xive2.c
> @@ -20,8 +20,8 @@
>  #include <bitmap.h>
>  #include <buddy.h>
>  #include <phys-map.h>
> -#include <p9_stop_api.H> /* TODO (p10): need P10 stop state engine */
> -
> +#include <p9_stop_api.H>
> +#include <p10_stop_api.H>

Why do we need both ? 

C. 

>  
>  /* Verbose debug */
>  #undef XIVE_VERBOSE_DEBUG
> @@ -3022,11 +3022,32 @@ static void xive_configure_ex_special_bar(struct xive *x, struct cpu_thread *c)
>  
>  void xive2_late_init(void)
>  {
> +	struct cpu_thread *c;
> +
>  	prlog(PR_INFO, "SLW: Configuring self-restore for NCU_SPEC_BAR\n");
> -			/*
> -			 * TODO (p10): need P10 stop state engine and fix for STOP11
> -			 */
> +	for_each_present_cpu(c) {
> +		if(cpu_is_thread0(c)) {
> +			struct proc_chip *chip = get_chip(c->chip_id);
> +			struct xive *x = chip->xive;
> +			uint64_t xa, val, rc;
> +			xa = XSCOM_ADDR_P10_NCU(pir_to_core_id(c->pir), P10_NCU_SPEC_BAR);
> +			val = (uint64_t)x->tm_base | P10_NCU_SPEC_BAR_ENABLE;
> +			/* Bail out if wakeup engine has already failed */
> +			if (wakeup_engine_state != WAKEUP_ENGINE_PRESENT) {
> +				prlog(PR_ERR, "XIVE proc_stop_api fail detected\n");
> +				break;
> +			}
> +			rc = proc_stop_save_scom((void *)chip->homer_base, xa, val,
> +				PROC_STOP_SCOM_REPLACE, PROC_STOP_SECTION_L3);
> +			if (rc) {
> +				xive_cpu_err(c, "proc_stop_save_scom failed for NCU_SPEC_BAR rc=%lld\n",
> +					     rc);
> +				wakeup_engine_state = WAKEUP_ENGINE_FAILED;
> +			}
> +		}
> +	}
>  }
> +
>  static void xive_provision_cpu(struct xive_cpu_state *xs, struct cpu_thread *c)
>  {
>  	struct xive *x;
>