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From: Matthew Dobson <colpatch@us.ibm.com>
To: Linus Torvalds <torvalds@transmeta.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
	"Martin J. Bligh" <Martin.Bligh@us.ibm.com>,
	linux-kernel@vger.kernel.org,
	Michael Hohnbaum <hohnbaum@us.ibm.com>,
	Greg KH <gregkh@us.ibm.com>,
	jgarzik@mandrakesoft.com, andrew.grover@intel.com,
	paul.s.diefenbaugh@intel.com
Subject: Re: [patch] PCI Cleanup
Date: Wed, 14 Aug 2002 17:23:24 -0700	[thread overview]
Message-ID: <3D5AF47C.3010305@us.ibm.com> (raw)
In-Reply-To: Pine.LNX.4.33.0208131545500.1277-100000@penguin.transmeta.com

[-- Attachment #1: Type: text/plain, Size: 1049 bytes --]

OK... Here's the latest version.  Sorry about that last posting... Stupid line 
wrapping broke the patch!  :(  This patch also removes the 
pci_config_(read|write) function pointers.  People shouldn't be using these (I 
don't think) and should be using the pci_ops structure linked through the 
pci_dev structure.  These end up calling the same functions that the 
pci_config_(read|write) pointers refer to anyway.  The only places I can see 
that these are being used in the kernel are in drivers/acpi/osl.c...  Anyone 
care to comment on the use there or if it can be changed?  I've cc'd the 
authors of the file...

A full version that fixes all arch's should be coming soon.

-Matt


Linus Torvalds wrote:
> On Tue, 13 Aug 2002, Matthew Dobson wrote:
> 
>>	I think I'm getting what you're aiming for here.  See if this patch comes close 
>>to what you're looking for.
> 
> 
> This seems to be more what I was thinking of, yes (although please drop 
> the "size_independent" part of the names, that just looks too horrible ;)
> 
> 		Linus
> 
> 


[-- Attachment #2: new_pci_fix-2531.patch --]
[-- Type: text/plain, Size: 14840 bytes --]

diff -Nur linux-2.5.31-vanilla/arch/i386/pci/common.c linux-2.5.31-patched/arch/i386/pci/common.c
--- linux-2.5.31-vanilla/arch/i386/pci/common.c	Sat Aug 10 18:41:27 2002
+++ linux-2.5.31-patched/arch/i386/pci/common.c	Wed Aug 14 10:57:40 2002
@@ -25,9 +25,6 @@
 struct pci_bus *pci_root_bus = NULL;
 struct pci_ops *pci_root_ops = NULL;
 
-int (*pci_config_read)(int seg, int bus, int dev, int fn, int reg, int len, u32 *value) = NULL;
-int (*pci_config_write)(int seg, int bus, int dev, int fn, int reg, int len, u32 value) = NULL;
-
 /*
  * legacy, numa, and acpi all want to call pcibios_scan_root
  * from their initcalls. This flag prevents that.
diff -Nur linux-2.5.31-vanilla/arch/i386/pci/direct.c linux-2.5.31-patched/arch/i386/pci/direct.c
--- linux-2.5.31-vanilla/arch/i386/pci/direct.c	Sat Aug 10 18:41:23 2002
+++ linux-2.5.31-patched/arch/i386/pci/direct.c	Tue Aug 13 16:28:13 2002
@@ -13,7 +13,7 @@
 #define PCI_CONF1_ADDRESS(bus, dev, fn, reg) \
 	(0x80000000 | (bus << 16) | (dev << 11) | (fn << 8) | (reg & ~3))
 
-static int pci_conf1_read (int seg, int bus, int dev, int fn, int reg, int len, u32 *value)
+static int __pci_conf1_read (int seg, int bus, int dev, int fn, int reg, int len, u32 *value)
 {
 	unsigned long flags;
 
@@ -41,7 +41,7 @@
 	return 0;
 }
 
-static int pci_conf1_write (int seg, int bus, int dev, int fn, int reg, int len, u32 value)
+static int __pci_conf1_write (int seg, int bus, int dev, int fn, int reg, int len, u32 value)
 {
 	unsigned long flags;
 
@@ -69,75 +69,23 @@
 	return 0;
 }
 
-
 #undef PCI_CONF1_ADDRESS
 
-static int pci_conf1_read_config_byte(struct pci_dev *dev, int where, u8 *value)
+static int pci_conf1_read(struct pci_dev *dev, int where, int size, u32 *value)
 {
-	int result; 
-	u32 data;
-
-	if (!value) 
-		return -EINVAL;
-
-	result = pci_conf1_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 1, &data);
-
-	*value = (u8)data;
-
-	return result;
+	return __pci_conf1_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
+		PCI_FUNC(dev->devfn), where, size, value);
 }
 
-static int pci_conf1_read_config_word(struct pci_dev *dev, int where, u16 *value)
+static int pci_conf1_write(struct pci_dev *dev, int where, int size, u32 value)
 {
-	int result; 
-	u32 data;
-
-	if (!value) 
-		return -EINVAL;
-
-	result = pci_conf1_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 2, &data);
-
-	*value = (u16)data;
-
-	return result;
-}
-
-static int pci_conf1_read_config_dword(struct pci_dev *dev, int where, u32 *value)
-{
-	if (!value) 
-		return -EINVAL;
-
-	return pci_conf1_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 4, value);
-}
-
-static int pci_conf1_write_config_byte(struct pci_dev *dev, int where, u8 value)
-{
-	return pci_conf1_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 1, value);
-}
-
-static int pci_conf1_write_config_word(struct pci_dev *dev, int where, u16 value)
-{
-	return pci_conf1_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 2, value);
-}
-
-static int pci_conf1_write_config_dword(struct pci_dev *dev, int where, u32 value)
-{
-	return pci_conf1_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 4, value);
+	return __pci_conf1_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
+		PCI_FUNC(dev->devfn), where, size, value);
 }
 
 static struct pci_ops pci_direct_conf1 = {
-	pci_conf1_read_config_byte,
-	pci_conf1_read_config_word,
-	pci_conf1_read_config_dword,
-	pci_conf1_write_config_byte,
-	pci_conf1_write_config_word,
-	pci_conf1_write_config_dword
+	read:	pci_conf1_read,
+	write:	pci_conf1_write
 };
 
 
@@ -147,7 +95,7 @@
 
 #define PCI_CONF2_ADDRESS(dev, reg)	(u16)(0xC000 | (dev << 8) | reg)
 
-static int pci_conf2_read (int seg, int bus, int dev, int fn, int reg, int len, u32 *value)
+static int __pci_conf2_read (int seg, int bus, int dev, int fn, int reg, int len, u32 *value)
 {
 	unsigned long flags;
 
@@ -181,7 +129,7 @@
 	return 0;
 }
 
-static int pci_conf2_write (int seg, int bus, int dev, int fn, int reg, int len, u32 value)
+static int __pci_conf2_write (int seg, int bus, int dev, int fn, int reg, int len, u32 value)
 {
 	unsigned long flags;
 
@@ -217,57 +165,21 @@
 
 #undef PCI_CONF2_ADDRESS
 
-static int pci_conf2_read_config_byte(struct pci_dev *dev, int where, u8 *value)
-{
-	int result; 
-	u32 data;
-	result = pci_conf2_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 1, &data);
-	*value = (u8)data;
-	return result;
-}
-
-static int pci_conf2_read_config_word(struct pci_dev *dev, int where, u16 *value)
-{
-	int result; 
-	u32 data;
-	result = pci_conf2_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 2, &data);
-	*value = (u16)data;
-	return result;
-}
-
-static int pci_conf2_read_config_dword(struct pci_dev *dev, int where, u32 *value)
-{
-	return pci_conf2_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 4, value);
-}
-
-static int pci_conf2_write_config_byte(struct pci_dev *dev, int where, u8 value)
+static int pci_conf2_read(struct pci_dev *dev, int where, int size, u32 *value)
 {
-	return pci_conf2_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 1, value);
+	return __pci_conf2_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
+		PCI_FUNC(dev->devfn), where, size, value);
 }
 
-static int pci_conf2_write_config_word(struct pci_dev *dev, int where, u16 value)
+static int pci_conf2_write(struct pci_dev *dev, int where, int size, u32 value)
 {
-	return pci_conf2_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 2, value);
-}
-
-static int pci_conf2_write_config_dword(struct pci_dev *dev, int where, u32 value)
-{
-	return pci_conf2_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 4, value);
+	return __pci_conf2_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
+		PCI_FUNC(dev->devfn), where, size, value);
 }
 
 static struct pci_ops pci_direct_conf2 = {
-	pci_conf2_read_config_byte,
-	pci_conf2_read_config_word,
-	pci_conf2_read_config_dword,
-	pci_conf2_write_config_byte,
-	pci_conf2_write_config_word,
-	pci_conf2_write_config_dword
+	read:	pci_conf2_read,
+	write:	pci_conf2_write
 };
 
 
@@ -283,7 +195,7 @@
  */
 static int __devinit pci_sanity_check(struct pci_ops *o)
 {
-	u16 x;
+	u32 x;
 	struct pci_bus bus;		/* Fake bus and device */
 	struct pci_dev dev;
 
@@ -292,16 +204,16 @@
 	bus.number = 0;
 	dev.bus = &bus;
 	for(dev.devfn=0; dev.devfn < 0x100; dev.devfn++)
-		if ((!o->read_word(&dev, PCI_CLASS_DEVICE, &x) &&
+		if ((!o->read(&dev, PCI_CLASS_DEVICE, 2, &x) &&
 		     (x == PCI_CLASS_BRIDGE_HOST || x == PCI_CLASS_DISPLAY_VGA)) ||
-		    (!o->read_word(&dev, PCI_VENDOR_ID, &x) &&
+		    (!o->read(&dev, PCI_VENDOR_ID, 2, &x) &&
 		     (x == PCI_VENDOR_ID_INTEL || x == PCI_VENDOR_ID_COMPAQ)))
 			return 1;
 	DBG("PCI: Sanity check failed\n");
 	return 0;
 }
 
-static struct pci_ops * __devinit pci_check_direct(void)
+static int __init pci_direct_init(void)
 {
 	unsigned int tmp;
 	unsigned long flags;
@@ -321,8 +233,10 @@
 			local_irq_restore(flags);
 			printk(KERN_INFO "PCI: Using configuration type 1\n");
 			if (!request_region(0xCF8, 8, "PCI conf1"))
-				return NULL;
-			return &pci_direct_conf1;
+				pci_root_ops = NULL;
+			else
+				pci_root_ops = &pci_direct_conf1;
+			return 0;
 		}
 		outl (tmp, 0xCF8);
 	}
@@ -339,28 +253,15 @@
 			local_irq_restore(flags);
 			printk(KERN_INFO "PCI: Using configuration type 2\n");
 			if (!request_region(0xCF8, 4, "PCI conf2"))
-				return NULL;
-			return &pci_direct_conf2;
+				pci_root_ops = NULL;
+			else
+				pci_root_ops = &pci_direct_conf2;
+			return 0;
 		}
 	}
 
 	local_irq_restore(flags);
-	return NULL;
-}
-
-static int __init pci_direct_init(void)
-{
-	if ((pci_probe & (PCI_PROBE_CONF1 | PCI_PROBE_CONF2)) 
-		&& (pci_root_ops = pci_check_direct())) {
-		if (pci_root_ops == &pci_direct_conf1) {
-			pci_config_read = pci_conf1_read;
-			pci_config_write = pci_conf1_write;
-		}
-		else {
-			pci_config_read = pci_conf2_read;
-			pci_config_write = pci_conf2_write;
-		}
-	}
+	pci_root_ops = NULL;
 	return 0;
 }
 
diff -Nur linux-2.5.31-vanilla/arch/i386/pci/pcbios.c linux-2.5.31-patched/arch/i386/pci/pcbios.c
--- linux-2.5.31-vanilla/arch/i386/pci/pcbios.c	Sat Aug 10 18:41:19 2002
+++ linux-2.5.31-patched/arch/i386/pci/pcbios.c	Wed Aug 14 10:55:20 2002
@@ -185,7 +185,7 @@
 	return (int) (ret & 0xff00) >> 8;
 }
 
-static int pci_bios_read (int seg, int bus, int dev, int fn, int reg, int len, u32 *value)
+static int __pci_bios_read (int seg, int bus, int dev, int fn, int reg, int len, u32 *value)
 {
 	unsigned long result = 0;
 	unsigned long flags;
@@ -240,7 +240,7 @@
 	return (int)((result & 0xff00) >> 8);
 }
 
-static int pci_bios_write (int seg, int bus, int dev, int fn, int reg, int len, u32 value)
+static int __pci_bios_write (int seg, int bus, int dev, int fn, int reg, int len, u32 value)
 {
 	unsigned long result = 0;
 	unsigned long flags;
@@ -295,63 +295,16 @@
 	return (int)((result & 0xff00) >> 8);
 }
 
-static int pci_bios_read_config_byte(struct pci_dev *dev, int where, u8 *value)
+static int pci_bios_read(struct pci_dev *dev, int where, int size, u32 *value)
 {
-	int result; 
-	u32 data;
-
-	if (!value) 
-		return -EINVAL;
-
-	result = pci_bios_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 1, &data);
-
-	*value = (u8)data;
-
-	return result;
-}
-
-static int pci_bios_read_config_word(struct pci_dev *dev, int where, u16 *value)
-{
-	int result; 
-	u32 data;
-
-	if (!value) 
-		return -EINVAL;
-
-	result = pci_bios_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 2, &data);
-
-	*value = (u16)data;
-
-	return result;
-}
-
-static int pci_bios_read_config_dword(struct pci_dev *dev, int where, u32 *value)
-{
-	if (!value) 
-		return -EINVAL;
-	
-	return pci_bios_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 4, value);
-}
-
-static int pci_bios_write_config_byte(struct pci_dev *dev, int where, u8 value)
-{
-	return pci_bios_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 1, value);
-}
-
-static int pci_bios_write_config_word(struct pci_dev *dev, int where, u16 value)
-{
-	return pci_bios_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 2, value);
+	return __pci_bios_read(0, dev->bus->number, PCI_SLOT(dev->devfn), 
+		PCI_FUNC(dev->devfn), where, size, value);
 }
 
-static int pci_bios_write_config_dword(struct pci_dev *dev, int where, u32 value)
+static int pci_bios_write(struct pci_dev *dev, int where, int size, u32 value)
 {
-	return pci_bios_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
-		PCI_FUNC(dev->devfn), where, 4, value);
+	return __pci_bios_write(0, dev->bus->number, PCI_SLOT(dev->devfn), 
+		PCI_FUNC(dev->devfn), where, size, value);
 }
 
 
@@ -360,12 +313,8 @@
  */
 
 static struct pci_ops pci_bios_access = {
-      pci_bios_read_config_byte,
-      pci_bios_read_config_word,
-      pci_bios_read_config_dword,
-      pci_bios_write_config_byte,
-      pci_bios_write_config_word,
-      pci_bios_write_config_dword
+      read:	pci_bios_read,
+      write:	pci_bios_write
 };
 
 /*
@@ -551,8 +500,6 @@
 		&& ((pci_root_ops = pci_find_bios()))) {
 		pci_probe |= PCI_BIOS_SORT;
 		pci_bios_present = 1;
-		pci_config_read = pci_bios_read;
-		pci_config_write = pci_bios_write;
 	}
 	return 0;
 }
diff -Nur linux-2.5.31-vanilla/drivers/pci/access.c linux-2.5.31-patched/drivers/pci/access.c
--- linux-2.5.31-vanilla/drivers/pci/access.c	Sat Aug 10 18:41:29 2002
+++ linux-2.5.31-patched/drivers/pci/access.c	Tue Aug 13 15:09:56 2002
@@ -19,24 +19,38 @@
 #define PCI_word_BAD (pos & 1)
 #define PCI_dword_BAD (pos & 3)
 
-#define PCI_OP(rw,size,type) \
-int pci_##rw##_config_##size (struct pci_dev *dev, int pos, type value) \
+#define PCI_OP_READ(size,type,len) \
+int pci_read_config_##size (struct pci_dev *dev, int pos, type *value) \
 {									\
 	int res;							\
 	unsigned long flags;						\
+	u32 data;							\
 	if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;	\
 	spin_lock_irqsave(&pci_lock, flags);				\
-	res = dev->bus->ops->rw##_##size(dev, pos, value);		\
+	res = dev->bus->ops->read(dev, pos, len, &data);		\
+	*value = (type)data;						\
 	spin_unlock_irqrestore(&pci_lock, flags);			\
 	return res;							\
 }
 
-PCI_OP(read, byte, u8 *)
-PCI_OP(read, word, u16 *)
-PCI_OP(read, dword, u32 *)
-PCI_OP(write, byte, u8)
-PCI_OP(write, word, u16)
-PCI_OP(write, dword, u32)
+#define PCI_OP_WRITE(size,type,len) \
+int pci_write_config_##size (struct pci_dev *dev, int pos, type value) \
+{									\
+	int res;							\
+	unsigned long flags;						\
+	if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;	\
+	spin_lock_irqsave(&pci_lock, flags);				\
+	res = dev->bus->ops->write(dev, pos, len, value);		\
+	spin_unlock_irqrestore(&pci_lock, flags);			\
+	return res;							\
+}
+
+PCI_OP_READ(byte, u8, 1)
+PCI_OP_READ(word, u16, 2)
+PCI_OP_READ(dword, u32, 4)
+PCI_OP_WRITE(byte, u8, 1)
+PCI_OP_WRITE(word, u16, 2)
+PCI_OP_WRITE(dword, u32, 4)
 
 EXPORT_SYMBOL(pci_read_config_byte);
 EXPORT_SYMBOL(pci_read_config_word);
diff -Nur linux-2.5.31-vanilla/include/asm-i386/pci.h linux-2.5.31-patched/include/asm-i386/pci.h
--- linux-2.5.31-vanilla/include/asm-i386/pci.h	Sat Aug 10 18:41:27 2002
+++ linux-2.5.31-patched/include/asm-i386/pci.h	Wed Aug 14 10:58:52 2002
@@ -22,8 +22,6 @@
 
 void pcibios_config_init(void);
 struct pci_bus * pcibios_scan_root(int bus);
-extern int (*pci_config_read)(int seg, int bus, int dev, int fn, int reg, int len, u32 *value);
-extern int (*pci_config_write)(int seg, int bus, int dev, int fn, int reg, int len, u32 value);
 
 void pcibios_set_master(struct pci_dev *dev);
 void pcibios_penalize_isa_irq(int irq);
diff -Nur linux-2.5.31-vanilla/include/linux/pci.h linux-2.5.31-patched/include/linux/pci.h
--- linux-2.5.31-vanilla/include/linux/pci.h	Sat Aug 10 18:41:28 2002
+++ linux-2.5.31-patched/include/linux/pci.h	Tue Aug 13 14:49:36 2002
@@ -456,12 +456,8 @@
 /* Low-level architecture-dependent routines */
 
 struct pci_ops {
-	int (*read_byte)(struct pci_dev *, int where, u8 *val);
-	int (*read_word)(struct pci_dev *, int where, u16 *val);
-	int (*read_dword)(struct pci_dev *, int where, u32 *val);
-	int (*write_byte)(struct pci_dev *, int where, u8 val);
-	int (*write_word)(struct pci_dev *, int where, u16 val);
-	int (*write_dword)(struct pci_dev *, int where, u32 val);
+	int (*read)(struct pci_dev *, int where, int size, u32 *val);
+	int (*write)(struct pci_dev *, int where, int size, u32 val);
 };
 
 struct pbus_set_ranges_data

  parent reply	other threads:[~2002-08-15  0:23 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-08-13  0:08 [patch] PCI Cleanup Matthew Dobson
2002-08-13 11:45 ` Alan Cox
2002-08-13 14:17   ` Martin J. Bligh
2002-08-13 14:57     ` Alan Cox
2002-08-13 15:15       ` Martin J. Bligh
2002-08-13 17:00       ` Matthew Dobson
2002-08-13 17:23         ` Linus Torvalds
2002-08-13 19:57           ` Martin J. Bligh
2002-08-13 20:13             ` Alan Cox
2002-08-13 20:26               ` Linus Torvalds
2002-08-13 22:29                 ` Matthew Dobson
2002-08-13 22:46                   ` Linus Torvalds
2002-08-14  0:57                     ` Matthew Dobson
2002-08-15  0:23                     ` Matthew Dobson [this message]
2002-08-14  7:08               ` Martin Mares
2002-08-13 14:55   ` Martin J. Bligh
2002-08-13 15:07     ` Alan Cox
  -- strict thread matches above, loose matches on Subject: below --
2002-08-15  2:24 Grover, Andrew
2002-08-15  7:49 ` Martin Mares
2002-08-15 15:58 ` Kai Germaschewski
2002-08-15 16:36   ` Greg KH
2002-08-16 22:34     ` Greg KH
2002-08-19 23:41       ` Matthew Dobson
2002-08-15 18:28 ` Patrick Mochel
2002-08-15 20:23 Grover, Andrew
2002-08-15 20:54 ` Patrick Mochel

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