> +#define CONTEXT_BITS 19 > +#define USER_ESID_BITS 18 > +#define USER_ESID_BITS_1T 6 > + > +/* > + * 256MB segment > + * The proto-VSID space has 2^(CONTEX_BITS + USER_ESID_BITS) - 1 segments > + * available for user + kernel mapping. The top 4 contexts are used for > + * kernel mapping. Each segment contains 2^28 bytes. Each > + * context maps 2^46 bytes (64TB) so we can support 2^19-1 contexts > + * (19 == 37 + 28 - 46). > + */
I can't help feeling this would be easier to understand if a full 64? 80? bit address was shown with the various bit ranges identified. Given the comment, I'd have expected CONTEXT_BITS to be calculated from three other named constants - rather than being set to 19. David _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev