Subject: Re: [PATCH] CAS DFP support

From: Jake Moilanen <[email-masked]>
Date: Wed, 22 Nov 2006 09:58:57 -0600

On Wed, 2006-11-22 at 09:46 -0600, Kumar Gala wrote:
> On Nov 22, 2006, at 9:20 AM, Jake Moilanen wrote:
> 
> > When booting a Power6 in compat mode, the DFP bit must be set in the
> > client architecture call, or else firmware will downgrade the  
> > compliance
> > to P5 compat mode, thus removing VMX and DFP instructions.
> >
> > Signed-off-by: Jake Moilanen <[email-masked]>
> >
> > --- 2.6/arch/powerpc/kernel/prom_init.c~	2006-11-13 15:01:13.000000000
> > -0600
> > +++ 2.6/arch/powerpc/kernel/prom_init.c	2006-11-21 18:38:27.000000000
> > -0600
> > @@ -627,6 +627,7 @@ static void __init early_cmdline_parse(v
> >  /* Option vector 3: processor options supported */
> >  #define OV3_FP			0x80	/* floating point */
> >  #define OV3_VMX			0x40	/* VMX/Altivec */
> > +#define OV3_DFP			0x20	/* decimal floating point */
> 
> Can we make the flag OV3_DECFP to distinguish it from Double FP.

Yup...

Signed-off-by: Jake Moilanen <[email-masked]>

--- 2.6/arch/powerpc/kernel/prom_init.c~	2006-11-13 15:01:13.000000000
-0600
+++ 2.6/arch/powerpc/kernel/prom_init.c	2006-11-21 18:38:27.000000000
-0600
@@ -627,6 +627,7 @@ static void __init early_cmdline_parse(v
 /* Option vector 3: processor options supported */
 #define OV3_FP			0x80	/* floating point */
 #define OV3_VMX			0x40	/* VMX/Altivec */
+#define OV3_DECFP			0x20	/* decimal floating point */
 
 /* Option vector 5: PAPR/OF options supported */
 #define OV5_LPAR		0x80	/* logical partitioning supported */
@@ -674,7 +675,7 @@ static unsigned char ibm_architecture_ve
 	/* option vector 3: processor options supported */
 	3 - 2,				/* length */
 	0,				/* don't ignore, don't halt */
-	OV3_FP | OV3_VMX,
+	OV3_FP | OV3_VMX | OV3_DECFP,
 
 	/* option vector 4: IBM PAPR implementation */
 	2 - 2,				/* length */