[Skiboot] [PATCH v6 1/2] phb4: set PHB CMPM registers for tunneled operations

[Frederic Barrat]

Le 14/02/2018 à 16:13, Philippe Bergheaud a écrit :
> P9 supports PCI tunneled operations (atomics and as_notify) that require
> setting the PHB ASN Compare/Mask register with a 16-bit indication.
> 
> This register is currently initialized by enable_capi_mode(). But, as
> tunneled operations may also work in PCI mode, the ASN Compare/Mask
> register should rather be initialized in phb4_init_ioda3().
> 
> This patch also adds "ibm,phb-indications" to the device tree, to tell
> Linux the values of CAPI, ASN, and NBW indications, when supported.
> 
> Tunneled operations tested by IBM in CAPI mode, by Mellanox Technologies
> in PCI mode.
> 
> Signed-off-by: Philippe Bergheaud <felix at linux.vnet.ibm.com>
> ---
> Changelog:
> 
> v2: Do not let Linux choose indication values.
>      Let skiboot tell Linux via the device tree.
>      Initialize the PHB ASN indication in PCI mode.
> 
> v3: No functional change.
>      Drop cosmetic fixes in comments.
> 
> v4: No change.
> 
> v5: Set bit 59 of ASN indication and mask, as required for as_notify,
>      in order to prevent address translation on lpid,pid,tid messages,
>      that are not real addresses.
> 
> v6: No change.
> ---
>   hw/phb4.c           | 28 +++++++++++++++++++++-------
>   include/phb4-regs.h |  4 ++--
>   2 files changed, 23 insertions(+), 9 deletions(-)
> 
> diff --git a/hw/phb4.c b/hw/phb4.c
> index 9748a1b7..83ee6de8 100644
> --- a/hw/phb4.c
> +++ b/hw/phb4.c
> @@ -3724,6 +3724,13 @@ static void phb4_init_capp_errors(struct phb4 *p)
>   	out_be64(p->regs + 0x0cb0,	0x35777073ff000000ull);
>   }
> 
> +#define CAPIIND		0x0200
> +#define CAPIMASK	0xFE00
> +#define ASNIND		0x0C00
> +#define ASNMASK		0xFFFF
> +#define NBWIND		0x0300
> +#define NBWMASK		0xF700

We need to explain those indicator and mask values, as it's getting 
touchy and I can't imagine remembering in a year. I'll send an initial 
version.


>   /* Power Bus Common Queue Registers
>    * All PBCQ and PBAIB registers are accessed via SCOM
>    * NestBase = 4010C00 for PEC0
> @@ -3810,16 +3817,13 @@ static int64_t enable_capi_mode(struct phb4 *p, uint64_t pe_number,
> 
>   	/*
>   	 * Bit [0:7] XSL_DSNCTL[capiind]
> -	 * Init_25 - CAPI Compare/Mask
> +	 * Init_26 - CAPI Compare/Mask
>   	 */
>   	out_be64(p->regs + PHB_CAPI_CMPM,
> -		 0x0200FE0000000000Ull | PHB_CAPI_CMPM_ENABLE);
> +		 ((u64)CAPIIND << 48) |
> +		 ((u64)CAPIMASK << 32) | PHB_CAPI_CMPM_ENABLE);
> 
>   	if (!(p->rev == PHB4_REV_NIMBUS_DD10)) {
> -		/* Init_24 - ASN Compare/Mask */
> -		out_be64(p->regs + PHB_PBL_ASN_CMPM,
> -			 0x0400FF0000000000Ull | PHB_PBL_ASN_ENABLE);
> -
>   		/* PBCQ Tunnel Bar Register
>   		 * Write Tunnel register to match PSL TNR register
>   		 */
> @@ -4141,7 +4145,10 @@ static void phb4_init_ioda3(struct phb4 *p)
>   	/* See enable_capi_mode() */
> 
>   	/* Init_25 - ASN Compare/Mask */
> -	/* See enable_capi_mode() */
> +	if (p->rev != PHB4_REV_NIMBUS_DD10)
> +		out_be64(p->regs + PHB_ASN_CMPM,
> +			 ((u64)ASNIND << 48) |
> +			 ((u64)ASNMASK << 32) | PHB_ASN_CMPM_ENABLE);

I think there's no need for new code to test for dd1. Nobody in the capi 
galaxy is using dd1 any more, so let's simplify.


>   	/* Init_26 - CAPI Compare/Mask */
>   	/* See enable_capi_mode() */
> @@ -4741,6 +4748,13 @@ static void phb4_add_properties(struct phb4 *p)
> 
>   	/* Indicate to Linux that CAPP timebase sync is supported */
>   	dt_add_property_string(np, "ibm,capp-timebase-sync", NULL);
> +
> +	/* Tell Linux Compare/Mask indication values */
> +	if (p->rev == PHB4_REV_NIMBUS_DD10)
> +		dt_add_property_cells(np, "ibm,phb-indications", CAPIIND, 0, 0);
> +	else
> +		dt_add_property_cells(np, "ibm,phb-indications", CAPIIND,
> +				      ASNIND, NBWIND);

Same comment as above.

   Fred

>   }
> 
>   static bool phb4_calculate_windows(struct phb4 *p)
> diff --git a/include/phb4-regs.h b/include/phb4-regs.h
> index 2dc64fe5..829d9ecb 100644
> --- a/include/phb4-regs.h
> +++ b/include/phb4-regs.h
> @@ -71,8 +71,8 @@
>   #define PHB_PEST_BAR			0x1a8
>   #define   PHB_PEST_BAR_ENABLE		PPC_BIT(0)
>   #define   PHB_PEST_BASE_ADDRESS		PPC_BITMASK(8,51)
> -#define PHB_PBL_ASN_CMPM		0x1C0
> -#define   PHB_PBL_ASN_ENABLE		PPC_BIT(63)
> +#define PHB_ASN_CMPM			0x1C0
> +#define   PHB_ASN_CMPM_ENABLE		PPC_BIT(63)
>   #define PHB_CAPI_CMPM			0x1C8
>   #define   PHB_CAPI_CMPM_ENABLE		PPC_BIT(63)
>   #define PHB_M64_UPPER_BITS		0x1f0
>