arch/tile: Allow tilegx to build with either 16K or 64K page size

This change introduces new flags for the hv_install_context()
API that passes a page table pointer to the hypervisor.  Clients
can explicitly request 4K, 16K, or 64K small pages when they
install a new context.  In practice, the page size is fixed at
kernel compile time and the same size is always requested every
time a new page table is installed.

The <hv/hypervisor.h> header changes so that it provides more abstract
macros for managing "page" things like PFNs and page tables.  For
example there is now a HV_DEFAULT_PAGE_SIZE_SMALL instead of the old
HV_PAGE_SIZE_SMALL.  The various PFN routines have been eliminated and
only PA- or PTFN-based ones remain (since PTFNs are always expressed
in fixed 2KB "page" size).  The page-table management macros are
renamed with a leading underscore and take page-size arguments with
the presumption that clients will use those macros in some single
place to provide the "real" macros they will use themselves.

I happened to notice the old hv_set_caching() API was totally broken
(it assumed 4KB pages) so I changed it so it would nominally work
correctly with other page sizes.

Tag modules with the page size so you can't load a module built with
a conflicting page size.  (And add a test for SMP while we're at it.)

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/arch/tile/include/asm/mmu_context.h b/arch/tile/include/asm/mmu_context.h
index 15fb246..37f0b74 100644
--- a/arch/tile/include/asm/mmu_context.h
+++ b/arch/tile/include/asm/mmu_context.h
@@ -30,11 +30,15 @@ init_new_context(struct task_struct *tsk, struct mm_struct *mm)
 	return 0;
 }
 
-/* Note that arch/tile/kernel/head.S also calls hv_install_context() */
+/*
+ * Note that arch/tile/kernel/head_NN.S and arch/tile/mm/migrate_NN.S
+ * also call hv_install_context().
+ */
 static inline void __install_page_table(pgd_t *pgdir, int asid, pgprot_t prot)
 {
 	/* FIXME: DIRECTIO should not always be set. FIXME. */
-	int rc = hv_install_context(__pa(pgdir), prot, asid, HV_CTX_DIRECTIO);
+	int rc = hv_install_context(__pa(pgdir), prot, asid,
+				    HV_CTX_DIRECTIO | CTX_PAGE_FLAG);
 	if (rc < 0)
 		panic("hv_install_context failed: %d", rc);
 }