From 63923d2c3800919774f5c651d503d1dd2adaddd5 Mon Sep 17 00:00:00 2001 From: John David Anglin Date: Mon, 27 May 2019 20:15:14 -0400 Subject: parisc: Use implicit space register selection for loading the coherence index of I/O pdirs We only support I/O to kernel space. Using %sr1 to load the coherence index may be racy unless interrupts are disabled. This patch changes the code used to load the coherence index to use implicit space register selection. This saves one instruction and eliminates the race. Tested on rp3440, c8000 and c3750. Signed-off-by: John David Anglin Cc: stable@vger.kernel.org Signed-off-by: Helge Deller --- drivers/parisc/sba_iommu.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/parisc/sba_iommu.c') diff --git a/drivers/parisc/sba_iommu.c b/drivers/parisc/sba_iommu.c index afaf8e6aefe6..78df92600203 100644 --- a/drivers/parisc/sba_iommu.c +++ b/drivers/parisc/sba_iommu.c @@ -575,8 +575,7 @@ sba_io_pdir_entry(u64 *pdir_ptr, space_t sid, unsigned long vba, pa = virt_to_phys(vba); pa &= IOVP_MASK; - mtsp(sid,1); - asm("lci 0(%%sr1, %1), %0" : "=r" (ci) : "r" (vba)); + asm("lci 0(%1), %0" : "=r" (ci) : "r" (vba)); pa |= (ci >> PAGE_SHIFT) & 0xff; /* move CI (8 bits) into lowest byte */ pa |= SBA_PDIR_VALID_BIT; /* set "valid" bit */ -- cgit v1.2.3