Re: [PATCH 1/3] powerpc/powernv/pci: Track largest available TCE order per PHB

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On Mon, 2 Jul 2018 17:32:56 +1000
Alexey Kardashevskiy <aik@ozlabs.ru> wrote:

> On Fri, 29 Jun 2018 17:34:35 +1000
> Russell Currey <ruscur@russell.cc> wrote:
> 
> > Knowing the largest possible TCE size of a PHB is useful, so get it
> > out of the device tree.  This relies on the property being added in
> > OPAL.
> > 
> > It is assumed that any PHB4 or later machine would be running
> > firmware that implemented this property, and otherwise assumed to
> > be PHB3, which has a maximum TCE order of 28 bits or 256MB TCEs.
> > 
> > This is used later in the series.
> > 
> > Signed-off-by: Russell Currey <ruscur@russell.cc>
> > ---
> >  arch/powerpc/platforms/powernv/pci-ioda.c | 16 ++++++++++++++++
> >  arch/powerpc/platforms/powernv/pci.h      |  3 +++
> >  2 files changed, 19 insertions(+)
> > 
> > diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c
> > b/arch/powerpc/platforms/powernv/pci-ioda.c index
> > 5bd0eb6681bc..17c590087279 100644 ---
> > a/arch/powerpc/platforms/powernv/pci-ioda.c +++
> > b/arch/powerpc/platforms/powernv/pci-ioda.c @@ -3873,11 +3873,13 @@
> > static void __init pnv_pci_init_ioda_phb(struct device_node *np,
> > struct resource r; const __be64 *prop64;
> >  	const __be32 *prop32;
> > +	struct property *prop;
> >  	int len;
> >  	unsigned int segno;
> >  	u64 phb_id;
> >  	void *aux;
> >  	long rc;
> > +	u32 val;
> >  
> >  	if (!of_device_is_available(np))
> >  		return;
> > @@ -4016,6 +4018,20 @@ static void __init
> > pnv_pci_init_ioda_phb(struct device_node *np, }
> >  	phb->ioda.pe_array = aux + pemap_off;
> >  
> > +	phb->ioda.max_tce_order = 0;
> > +	/* Get TCE order from the DT.  If it's not present, assume
> > P8 */
> > +	if (!of_get_property(np, "ibm,supported-tce-sizes", NULL))
> > {
> > +		phb->ioda.max_tce_order = 28; /* assume P8 256mb
> > TCEs */
> > +	} else {
> > +		of_property_for_each_u32(np,
> > "ibm,supported-tce-sizes", prop,
> > +					 prop32, val) {
> > +			if (val > phb->ioda.max_tce_order)
> > +				phb->ioda.max_tce_order = val;
> > +		}
> > +		pr_debug("PHB%llx Found max TCE order of %d
> > bits\n",
> > +			 phb->opal_id, phb->ioda.max_tce_order);
> > +	}  
> 
> 
> pnv_ioda_parse_tce_sizes() does this, use it. It even reports 256MB
> pages for P8 as in v4.18-rc3.


ah, not, not in rc3, my bad. I'll post it soon.


--
Alexey