Re: [PATCH 04/15] powerpc/powernv/pci: Initialise M64 for IODA1 as a 1-1 window

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 10/07/2020 15:23, Oliver O'Halloran wrote:
> We pre-configure the m64 window for IODA1 as a 1-1 segment-PE mapping,
> similar to PHB3. Currently the actual mapping of segments occurs in
> pnv_ioda_pick_m64_pe(), but we can move it into pnv_ioda1_init_m64() and
> drop the IODA1 specific code paths in the PE setup / teardown.
> 
> Signed-off-by: Oliver O'Halloran <oohall@gmail.com>



Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>


> ---
>  arch/powerpc/platforms/powernv/pci-ioda.c | 55 +++++++++++------------
>  1 file changed, 25 insertions(+), 30 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
> index bb9c1cc60c33..8fb17676d914 100644
> --- a/arch/powerpc/platforms/powernv/pci-ioda.c
> +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
> @@ -311,6 +311,28 @@ static int pnv_ioda1_init_m64(struct pnv_phb *phb)
>  		}
>  	}
>  
> +	for (index = 0; index < phb->ioda.total_pe_num; index++) {
> +		int64_t rc;
> +
> +		/*
> +		 * P7IOC supports M64DT, which helps mapping M64 segment
> +		 * to one particular PE#. However, PHB3 has fixed mapping
> +		 * between M64 segment and PE#. In order to have same logic
> +		 * for P7IOC and PHB3, we enforce fixed mapping between M64
> +		 * segment and PE# on P7IOC.
> +		 */
> +		rc = opal_pci_map_pe_mmio_window(phb->opal_id,
> +				index, OPAL_M64_WINDOW_TYPE,
> +				index / PNV_IODA1_M64_SEGS,
> +				index % PNV_IODA1_M64_SEGS);
> +		if (rc != OPAL_SUCCESS) {
> +			pr_warn("%s: Error %lld mapping M64 for PHB#%x-PE#%x\n",
> +				__func__, rc, phb->hose->global_number,
> +				index);
> +			goto fail;
> +		}
> +	}
> +
>  	/*
>  	 * Exclude the segments for reserved and root bus PE, which
>  	 * are first or last two PEs.
> @@ -402,26 +424,6 @@ static struct pnv_ioda_pe *pnv_ioda_pick_m64_pe(struct pci_bus *bus, bool all)
>  			pe->master = master_pe;
>  			list_add_tail(&pe->list, &master_pe->slaves);
>  		}
> -
> -		/*
> -		 * P7IOC supports M64DT, which helps mapping M64 segment
> -		 * to one particular PE#. However, PHB3 has fixed mapping
> -		 * between M64 segment and PE#. In order to have same logic
> -		 * for P7IOC and PHB3, we enforce fixed mapping between M64
> -		 * segment and PE# on P7IOC.
> -		 */
> -		if (phb->type == PNV_PHB_IODA1) {
> -			int64_t rc;
> -
> -			rc = opal_pci_map_pe_mmio_window(phb->opal_id,
> -					pe->pe_number, OPAL_M64_WINDOW_TYPE,
> -					pe->pe_number / PNV_IODA1_M64_SEGS,
> -					pe->pe_number % PNV_IODA1_M64_SEGS);
> -			if (rc != OPAL_SUCCESS)
> -				pr_warn("%s: Error %lld mapping M64 for PHB#%x-PE#%x\n",
> -					__func__, rc, phb->hose->global_number,
> -					pe->pe_number);
> -		}
>  	}
>  
>  	kfree(pe_alloc);
> @@ -3354,14 +3356,8 @@ static void pnv_ioda_free_pe_seg(struct pnv_ioda_pe *pe,
>  		if (map[idx] != pe->pe_number)
>  			continue;
>  
> -		if (win == OPAL_M64_WINDOW_TYPE)
> -			rc = opal_pci_map_pe_mmio_window(phb->opal_id,
> -					phb->ioda.reserved_pe_idx, win,
> -					idx / PNV_IODA1_M64_SEGS,
> -					idx % PNV_IODA1_M64_SEGS);
> -		else
> -			rc = opal_pci_map_pe_mmio_window(phb->opal_id,
> -					phb->ioda.reserved_pe_idx, win, 0, idx);
> +		rc = opal_pci_map_pe_mmio_window(phb->opal_id,
> +				phb->ioda.reserved_pe_idx, win, 0, idx);
>  
>  		if (rc != OPAL_SUCCESS)
>  			pe_warn(pe, "Error %lld unmapping (%d) segment#%d\n",
> @@ -3380,8 +3376,7 @@ static void pnv_ioda_release_pe_seg(struct pnv_ioda_pe *pe)
>  				     phb->ioda.io_segmap);
>  		pnv_ioda_free_pe_seg(pe, OPAL_M32_WINDOW_TYPE,
>  				     phb->ioda.m32_segmap);
> -		pnv_ioda_free_pe_seg(pe, OPAL_M64_WINDOW_TYPE,
> -				     phb->ioda.m64_segmap);
> +		/* M64 is pre-configured by pnv_ioda1_init_m64() */
>  	} else if (phb->type == PNV_PHB_IODA2) {
>  		pnv_ioda_free_pe_seg(pe, OPAL_M32_WINDOW_TYPE,
>  				     phb->ioda.m32_segmap);
> 

-- 
Alexey