[src/trunk]: src/sys/arch/x86/pci Make the override implementation more conci...

[dyoung <dyoung%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/286bb6ec91c8
branches:  trunk
changeset: 768855:286bb6ec91c8
user:      dyoung <dyoung%NetBSD.org@localhost>
date:      Sun Aug 28 04:59:37 2011 +0000

description:
Make the override implementation more concise.  Saves about three lines
of code per routine, makes it more explicit what's going on, and avoids
recursion, though the compiler probably optimized the tail recursion in
the old code.

diffstat:

 sys/arch/x86/pci/pci_machdep.c |  65 +++++++++++++++++------------------------
 1 files changed, 27 insertions(+), 38 deletions(-)

diffs (119 lines):

diff -r c4f0aaca53d3 -r 286bb6ec91c8 sys/arch/x86/pci/pci_machdep.c
--- a/sys/arch/x86/pci/pci_machdep.c    Sun Aug 28 03:54:07 2011 +0000
+++ b/sys/arch/x86/pci/pci_machdep.c    Sun Aug 28 04:59:37 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pci_machdep.c,v 1.46 2011/08/27 09:32:11 christos Exp $        */
+/*     $NetBSD: pci_machdep.c,v 1.47 2011/08/28 04:59:37 dyoung Exp $  */
 
 /*-
  * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
@@ -73,7 +73,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pci_machdep.c,v 1.46 2011/08/27 09:32:11 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pci_machdep.c,v 1.47 2011/08/28 04:59:37 dyoung Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -418,17 +418,14 @@
 pcitag_t
 pci_make_tag(pci_chipset_tag_t pc, int bus, int device, int function)
 {
+       pci_chipset_tag_t ipc;
        pcitag_t tag;
 
-       if (pc != NULL) {
-               if ((pc->pc_present & PCI_OVERRIDE_MAKE_TAG) != 0) {
-                       return (*pc->pc_ov->ov_make_tag)(pc->pc_ctx,
-                           pc, bus, device, function);
-               }
-               if (pc->pc_super != NULL) {
-                       return pci_make_tag(pc->pc_super, bus, device,
-                           function);
-               }
+       for (ipc = pc; ipc != NULL; ipc = ipc->pc_super) {
+               if ((ipc->pc_present & PCI_OVERRIDE_MAKE_TAG) == 0)
+                       continue;
+               return (*ipc->pc_ov->ov_make_tag)(ipc->pc_ctx,
+                   pc, bus, device, function);
        }
 
        switch (pci_mode) {
@@ -456,17 +453,14 @@
 pci_decompose_tag(pci_chipset_tag_t pc, pcitag_t tag,
     int *bp, int *dp, int *fp)
 {
+       pci_chipset_tag_t ipc;
 
-       if (pc != NULL) {
-               if ((pc->pc_present & PCI_OVERRIDE_DECOMPOSE_TAG) != 0) {
-                       (*pc->pc_ov->ov_decompose_tag)(pc->pc_ctx,
-                           pc, tag, bp, dp, fp);
-                       return;
-               }
-               if (pc->pc_super != NULL) {
-                       pci_decompose_tag(pc->pc_super, tag, bp, dp, fp);
-                       return;
-               }
+       for (ipc = pc; ipc != NULL; ipc = ipc->pc_super) {
+               if ((ipc->pc_present & PCI_OVERRIDE_DECOMPOSE_TAG) == 0)
+                       continue;
+               (*ipc->pc_ov->ov_decompose_tag)(ipc->pc_ctx,
+                   pc, tag, bp, dp, fp);
+               return;
        }
 
        switch (pci_mode) {
@@ -494,18 +488,16 @@
 pcireg_t
 pci_conf_read(pci_chipset_tag_t pc, pcitag_t tag, int reg)
 {
+       pci_chipset_tag_t ipc;
        pcireg_t data;
        struct pci_conf_lock ocl;
 
        KASSERT((reg & 0x3) == 0);
 
-       if (pc != NULL) {
-               if ((pc->pc_present & PCI_OVERRIDE_CONF_READ) != 0) {
-                       return (*pc->pc_ov->ov_conf_read)(pc->pc_ctx,
-                           pc, tag, reg);
-               }
-               if (pc->pc_super != NULL)
-                       return pci_conf_read(pc->pc_super, tag, reg);
+       for (ipc = pc; ipc != NULL; ipc = ipc->pc_super) {
+               if ((ipc->pc_present & PCI_OVERRIDE_CONF_READ) == 0)
+                       continue;
+               return (*ipc->pc_ov->ov_conf_read)(ipc->pc_ctx, pc, tag, reg);
        }
 
 #if defined(__i386__) && defined(XBOX)
@@ -526,20 +518,17 @@
 void
 pci_conf_write(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t data)
 {
+       pci_chipset_tag_t ipc;
        struct pci_conf_lock ocl;
 
        KASSERT((reg & 0x3) == 0);
 
-       if (pc != NULL) {
-               if ((pc->pc_present & PCI_OVERRIDE_CONF_WRITE) != 0) {
-                       (*pc->pc_ov->ov_conf_write)(pc->pc_ctx, pc, tag, reg,
-                           data);
-                       return;
-               }
-               if (pc->pc_super != NULL) {
-                       pci_conf_write(pc->pc_super, tag, reg, data);
-                       return;
-               }
+       for (ipc = pc; ipc != NULL; ipc = ipc->pc_super) {
+               if ((ipc->pc_present & PCI_OVERRIDE_CONF_WRITE) == 0)
+                       continue;
+               (*ipc->pc_ov->ov_conf_write)(ipc->pc_ctx, pc, tag, reg,
+                   data);
+               return;
        }
 
 #if defined(__i386__) && defined(XBOX)