From 88314ee73fd75eb32abdcb3119cd303c116d4500 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 31 May 2005 19:13:52 -0700 Subject: [PATCH] [SPARC64]: Refine PCI strbuf ctx-based flush. The initial peek read PIO of the match register is just a waste. Just do the flush writes first, as that is more efficient. Signed-off-by: David S. Miller --- arch/sparc64/kernel/pci_iommu.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/arch/sparc64/kernel/pci_iommu.c b/arch/sparc64/kernel/pci_iommu.c index 1807876f8c36..2803bc7c2c79 100644 --- a/arch/sparc64/kernel/pci_iommu.c +++ b/arch/sparc64/kernel/pci_iommu.c @@ -422,14 +422,12 @@ static void pci_strbuf_flush(struct pci_strbuf *strbuf, struct pci_iommu *iommu, flushreg = strbuf->strbuf_ctxflush; matchreg = PCI_STC_CTXMATCH_ADDR(strbuf, ctx); - if (pci_iommu_read(matchreg) == 0) - goto do_flush_sync; - pci_iommu_write(flushreg, ctx); - if ((val = pci_iommu_read(matchreg)) == 0) + val = pci_iommu_read(matchreg); + val &= 0xffff; + if (!val) goto do_flush_sync; - val &= 0xffff; while (val) { if (val & 0x1) pci_iommu_write(flushreg, ctx); -- 2.20.1