Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/qe_ic: Fix another breakage from the irq_data conversion
  powerpc/8xx: Fix another breakage from the irq_data conversion
  powerpc/cell: Use handle_edge_eoi_irq for real
  powerpc/pseries: Enable Chelsio network and iWARP drivers
  powerpc/mm: Move the STAB0 location to 0x8000 to make room in low memory
  powerpc: Fix accounting of softirq time when idle
  powerpc/pseries/smp: query-cpu-stopped-state support won't change
  powerpc/xics: Use hwirq for xics domain irq number
  powerpc/xics: Fix numberspace mismatch from irq_desc conversion
  powerpc: Wire up new syscalls
  powerpc/booke: Correct the SPRN_MAS5 definition.
  powerpc: ARCH_PFN_OFFSET should be unsigned long
  powerpc: Implement dma_mmap_coherent()
  powerpc/nvram: Don't overwrite oops/panic report on normal shutdown
  powerpc: Restore some misc devices to our configs

1 files changed, 20 insertions, 0 deletions

diff --git a/arch/powerpc/mm/dma-noncoherent.c b/arch/powerpc/mm/dma-noncoherent.c
index 757c0bed9a9..b42f76c4948 100644
--- a/arch/powerpc/mm/dma-noncoherent.c
+++ b/arch/powerpc/mm/dma-noncoherent.c
@@ -399,3 +399,23 @@ void __dma_sync_page(struct page *page, unsigned long offset,
 #endif
 }
 EXPORT_SYMBOL(__dma_sync_page);
+
+/*
+ * Return the PFN for a given cpu virtual address returned by
+ * __dma_alloc_coherent. This is used by dma_mmap_coherent()
+ */
+unsigned long __dma_get_coherent_pfn(unsigned long cpu_addr)
+{
+	/* This should always be populated, so we don't test every
+	 * level. If that fails, we'll have a nice crash which
+	 * will be as good as a BUG_ON()
+	 */
+	pgd_t *pgd = pgd_offset_k(cpu_addr);
+	pud_t *pud = pud_offset(pgd, cpu_addr);
+	pmd_t *pmd = pmd_offset(pud, cpu_addr);
+	pte_t *ptep = pte_offset_kernel(pmd, cpu_addr);
+
+	if (pte_none(*ptep) || !pte_present(*ptep))
+		return 0;
+	return pte_pfn(*ptep);
+}