[Skiboot] [PATCH 2/2] SCOM restore for DARN and XIVE

[Michael Neuling]

The subject needs to mention SLW/stop.

Mikey


On Thu, 2017-11-16 at 08:49 +0530, Akshay Adiga wrote:
> While waking up from stop11, we want NCU_DARN_BAR to have enable bit set.
> Without this stop_api call, the value restored is without enable bit set.
> We loose NCU_SPEC_BAR when the quad goes into stop11, stop_api will
> restore while waking up from stop11.
> 
> Signed-off-by: Akshay Adiga <akshay.adiga at linux.vnet.ibm.com>
> ---
> Changes from initial posting
> * Changed flag P9_STOP_SECTION_CORE_SCOM to P9_STOP_SECTION_EQ_SCOM
>  for P9X_EX_NCU_DARN_BAR
> * Added error handling
> 
>  hw/nx.c   | 15 ++++++++++++++-
>  hw/xive.c | 10 ++++++++++
>  2 files changed, 24 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/nx.c b/hw/nx.c
> index 64ac793..e130317 100644
> --- a/hw/nx.c
> +++ b/hw/nx.c
> @@ -24,6 +24,7 @@
>  #include <chip.h>
>  #include <xscom-p9-regs.h>
>  #include <phys-map.h>
> +#include <p9_stop_api.H>
>  
>  extern void nx_p9_rng_init(void);
>  
> @@ -31,7 +32,7 @@ void nx_p9_rng_init(void)
>  {
>  	struct proc_chip *chip;
>  	struct cpu_thread *c;
> -	uint64_t bar, tmp;
> +	uint64_t bar, tmp, rc;
>  
>  	if (proc_gen != proc_gen_p9)
>  		return;
> @@ -65,6 +66,18 @@ void nx_p9_rng_init(void)
>  						P9X_EX_NCU_DARN_BAR);
>  			xscom_write(chip->id, addr,
>  				    bar | P9X_EX_NCU_DARN_BAR_EN);
> +			rc = p9_stop_save_scom((void *)chip->homer_base,
> +					addr, bar | P9X_EX_NCU_DARN_BAR_EN,
> +					P9_STOP_SCOM_REPLACE,
> +					P9_STOP_SECTION_EQ_SCOM);
> +			if (rc) {
> +				prlog(PR_ERR,
> +				"p9_stop_api for DARN_BAR failed rc= %lld",
> +				 rc);
> +				prlog(PR_ERR, "Disabling deep stop
> states\n");
> +				chip->wakeup_engine_error = true;
> +			}
> +
>  		}
>  	}
>  }
> diff --git a/hw/xive.c b/hw/xive.c
> index df38074..14363b0 100644
> --- a/hw/xive.c
> +++ b/hw/xive.c
> @@ -24,6 +24,7 @@
>  #include <bitmap.h>
>  #include <buddy.h>
>  #include <phys-map.h>
> +#include <p9_stop_api.H>
>  
>  /* Use Block group mode to move chip_id into block .... */
>  #define USE_BLOCK_GROUP_MODE
> @@ -3136,6 +3137,7 @@ static void xive_configure_ex_special_bar(struct xive
> *x, struct cpu_thread *c)
>  {
>  	uint64_t xa, val;
>  	int64_t rc;
> +	struct proc_chip *chip = get_chip(c->chip_id);
>  
>  	xive_cpu_dbg(c, "Setting up special BAR\n");
>  	xa = XSCOM_ADDR_P9_EX(pir_to_core_id(c->pir), P9X_EX_NCU_SPEC_BAR);
> @@ -3148,6 +3150,14 @@ static void xive_configure_ex_special_bar(struct xive
> *x, struct cpu_thread *c)
>  		xive_cpu_err(c, "Failed to setup NCU_SPEC_BAR\n");
>  		/* XXXX  what do do now ? */
>  	}
> +	rc = p9_stop_save_scom((void *)chip->homer_base, xa, val,
> +				P9_STOP_SCOM_REPLACE,
> P9_STOP_SECTION_EQ_SCOM);
> +	if (rc) {
> +		xive_cpu_err(c, "p9_stop_api failed for NCU_SPEC_BAR
> rc=%lld\n",
> +				rc);
> +		xive_cpu_err(c, "Disabling deep idle states\n");
> +		chip->wakeup_engine_error = true;
> +	}
>  }
>  
>  static void xive_provision_cpu(struct xive_cpu_state *xs, struct cpu_thread
> *c)