Re: [PATCH 0/2] eisa: fix eisa with PCI

Re: [PATCH 0/2] eisa: fix eisa with PCI

[Bjorn Helgaas]

[+cc linux-pci]

On Wed, Mar 27, 2013 at 10:28 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> Looks like pci eisa bridge support is broken for a while.
>
> one is root io resource reference, and other one is pnp related.
>
> Please check if we can put them in v3.9.
>         eisa, PCI: Fix bus res reference
>         eisa, PCI: init eisa early before pnp step in

Both of these patches are to drivers/eisa/pci_eisa.c.  I don't see an
EISA-specific maintainer, and I caused at least one of these problems,
so I'll push these through my PCI tree unless somebody objects.

Bjorn

Re: [PATCH 0/2] eisa: fix eisa with PCI

[Bjorn Helgaas]

[-- Attachment #1: Type: text/plain, Size: 952 bytes --]

On Fri, Mar 29, 2013 at 9:16 AM, Bjorn Helgaas <bhelgaas@google.com> wrote:
> [+cc linux-pci]
>
> On Wed, Mar 27, 2013 at 10:28 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>> Looks like pci eisa bridge support is broken for a while.
>>
>> one is root io resource reference, and other one is pnp related.
>>
>> Please check if we can put them in v3.9.
>>         eisa, PCI: Fix bus res reference
>>         eisa, PCI: init eisa early before pnp step in
>
> Both of these patches are to drivers/eisa/pci_eisa.c.  I don't see an
> EISA-specific maintainer, and I caused at least one of these problems,
> so I'll push these through my PCI tree unless somebody objects.

Hi Matthew,

Can you test either the attached patch (against v3.9-rc4) or the git
tree at http://git.kernel.org/cgit/linux/kernel/git/helgaas/pci.git/log/?h=pci/yinghai-eisa
and send me the complete dmesg log?

If all goes well, I'll ask Linus to pull these before v3.9.

Thanks!

Bjorn

[-- Attachment #2: eisa.patch --]
[-- Type: application/octet-stream, Size: 11443 bytes --]

commit 2cfda637e29ce9e3df31b59f64516b2e571cc985
Author: Yinghai Lu <yinghai@kernel.org>
Date:   Mon Apr 1 11:48:59 2013 -0600

    EISA/PCI: Fix bus res reference
    
    Matthew found that 3.8.3 is having problems with an old (ancient)
    PCI-to-EISA bridge, the Intel 82375. It worked with the 3.2 kernel.
    He identified the 82375, but doesn't assign the struct resource *res
    pointer inside the struct eisa_root_device, and panics.
    
    pci_eisa_init() was using bus->resource[] directly instead of
    pci_bus_resource_n().  The bus->resource[] array is a PCI-internal
    implementation detail, and after commit 45ca9e97 (PCI: add helpers for
    building PCI bus resource lists) and commit 0efd5aab (PCI: add struct
    pci_host_bridge_window with CPU/bus address offset), bus->resource[] is not
    used for PCI root buses any more.
    
    The 82375 is a subtractive-decode PCI device, so handle it the same
    way we handle PCI-PCI bridges in subtractive-decode mode in
    pci_read_bridge_bases().
    
    [bhelgaas: changelog]
    Reported-by: Matthew Whitehead <mwhitehe@redhat.com>
    Tested-by: Matthew Whitehead <mwhitehe@redhat.com>
    Signed-off-by: Yinghai Lu <yinghai@kernel.org>
    Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
    Cc: stable@vger.kernel.org	# v3.3+

diff --git a/drivers/eisa/pci_eisa.c b/drivers/eisa/pci_eisa.c
index cdae207..ef5c3ec 100644
--- a/drivers/eisa/pci_eisa.c
+++ b/drivers/eisa/pci_eisa.c
@@ -22,7 +22,8 @@ static struct eisa_root_device pci_eisa_root;
 static int __init pci_eisa_init(struct pci_dev *pdev,
 				const struct pci_device_id *ent)
 {
-	int rc;
+	int rc, i;
+	struct resource *res, *bus_res = NULL;
 
 	if ((rc = pci_enable_device (pdev))) {
 		printk (KERN_ERR "pci_eisa : Could not enable device %s\n",
@@ -30,9 +31,30 @@ static int __init pci_eisa_init(struct pci_dev *pdev,
 		return rc;
 	}
 
+	/*
+	 * The Intel 82375 PCI-EISA bridge is a subtractive-decode PCI
+	 * device, so the resources available on EISA are the same as those
+	 * available on the 82375 bus.  This works the same as a PCI-PCI
+	 * bridge in subtractive-decode mode (see pci_read_bridge_bases()).
+	 * We assume other PCI-EISA bridges are similar.
+	 *
+	 * eisa_root_register() can only deal with a single io port resource,
+	*  so we use the first valid io port resource.
+	 */
+	pci_bus_for_each_resource(pdev->bus, res, i)
+		if (res && (res->flags & IORESOURCE_IO)) {
+			bus_res = res;
+			break;
+		}
+
+	if (!bus_res) {
+		dev_err(&pdev->dev, "No resources available\n");
+		return -1;
+	}
+
 	pci_eisa_root.dev              = &pdev->dev;
-	pci_eisa_root.res	       = pdev->bus->resource[0];
-	pci_eisa_root.bus_base_addr    = pdev->bus->resource[0]->start;
+	pci_eisa_root.res	       = bus_res;
+	pci_eisa_root.bus_base_addr    = bus_res->start;
 	pci_eisa_root.slots	       = EISA_MAX_SLOTS;
 	pci_eisa_root.dma_mask         = pdev->dma_mask;
 	dev_set_drvdata(pci_eisa_root.dev, &pci_eisa_root);

commit c5fb301ae83bec6892e54984e6ec765c47df8e10
Author: Yinghai Lu <yinghai@kernel.org>
Date:   Wed Mar 27 21:28:05 2013 -0700

    EISA/PCI: Init EISA early, before PNP
    
    Matthew reported kernels fail the pci_eisa probe and are later successful
    with the virtual_eisa_root_init force probe without slot0.
    
    The reason for that is: PNP probing is before pci_eisa_init gets called
    as pci_eisa_init is called via pci_driver.
    
    pnp 00:0f has 0xc80 - 0xc84 reserved.
    [    9.700409] pnp 00:0f: [io  0x0c80-0x0c84]
    
    so eisa_probe will fail from pci_eisa_init
    				==>eisa_root_register
    					==>eisa_probe path.
    as force_probe is not set in pci_eisa_root, it will bail early when
    slot0 is not probed and initialized.
    
    Try to use subsys_initcall_sync instead, and will keep following sequence:
    	pci_subsys_init
    	pci_eisa_init_early
    	pnpacpi_init/isapnp_init
    
    After this patch EISA can be initialized properly, and PNP overlapping
    resource will not be reserved.
    [   10.104434] system 00:0f: [io  0x0c80-0x0c84] could not be reserved
    
    Reported-by: Matthew Whitehead <mwhitehe@redhat.com>
    Tested-by: Matthew Whitehead <mwhitehe@redhat.com>
    Signed-off-by: Yinghai Lu <yinghai@kernel.org>
    Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
    Cc: stable@vger.kernel.org

diff --git a/drivers/eisa/pci_eisa.c b/drivers/eisa/pci_eisa.c
index ef5c3ec..6c3fca9 100644
--- a/drivers/eisa/pci_eisa.c
+++ b/drivers/eisa/pci_eisa.c
@@ -19,8 +19,7 @@
 /* There is only *one* pci_eisa device per machine, right ? */
 static struct eisa_root_device pci_eisa_root;
 
-static int __init pci_eisa_init(struct pci_dev *pdev,
-				const struct pci_device_id *ent)
+static int __init pci_eisa_init(struct pci_dev *pdev)
 {
 	int rc, i;
 	struct resource *res, *bus_res = NULL;
@@ -67,22 +66,26 @@ static int __init pci_eisa_init(struct pci_dev *pdev,
 	return 0;
 }
 
-static struct pci_device_id pci_eisa_pci_tbl[] = {
-	{ PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
-	  PCI_CLASS_BRIDGE_EISA << 8, 0xffff00, 0 },
-	{ 0, }
-};
+/*
+ * We have to call pci_eisa_init_early() before pnpacpi_init()/isapnp_init().
+ *   Otherwise pnp resource will get enabled early and could prevent eisa
+ *   to be initialized.
+ * Also need to make sure pci_eisa_init_early() is called after
+ * x86/pci_subsys_init().
+ * So need to use subsys_initcall_sync with it.
+ */
+static int __init pci_eisa_init_early(void)
+{
+	struct pci_dev *dev = NULL;
+	int ret;
 
-static struct pci_driver __refdata pci_eisa_driver = {
-	.name		= "pci_eisa",
-	.id_table	= pci_eisa_pci_tbl,
-	.probe		= pci_eisa_init,
-};
+	for_each_pci_dev(dev)
+		if ((dev->class >> 8) == PCI_CLASS_BRIDGE_EISA) {
+			ret = pci_eisa_init(dev);
+			if (ret)
+				return ret;
+		}
 
-static int __init pci_eisa_init_module (void)
-{
-	return pci_register_driver (&pci_eisa_driver);
+	return 0;
 }
-
-device_initcall(pci_eisa_init_module);
-MODULE_DEVICE_TABLE(pci, pci_eisa_pci_tbl);
+subsys_initcall_sync(pci_eisa_init_early);

commit d0e36df69863bfa054a4703406a737b0476e68e8
Author: Bjorn Helgaas <bhelgaas@google.com>
Date:   Mon Apr 1 14:16:56 2013 -0600

    EISA: Use dev_printk() when possible
    
    Use dev_printk() when possible to make messages more useful.
    
    Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/eisa/eisa-bus.c b/drivers/eisa/eisa-bus.c
index 806c77b..0b06df4 100644
--- a/drivers/eisa/eisa-bus.c
+++ b/drivers/eisa/eisa-bus.c
@@ -314,22 +314,22 @@ static int __init eisa_probe(struct eisa_root_device *root)
 {
         int i, c;
 	struct eisa_device *edev;
+	char *enabled_str;
 
-	printk(KERN_INFO "EISA: Probing bus %d at %s\n",
-	       root->bus_nr, dev_name(root->dev));
+	dev_info(root->dev, "Probing EISA bus %d\n", root->bus_nr);
 
 	/* First try to get hold of slot 0. If there is no device
 	 * here, simply fail, unless root->force_probe is set. */
 	
 	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
 	if (!edev) {
-		printk(KERN_ERR "EISA: Couldn't allocate mainboard slot\n");
+		dev_err(root->dev, "EISA: Couldn't allocate mainboard slot\n");
 		return -ENOMEM;
 	}
 		
 	if (eisa_request_resources(root, edev, 0)) {
-		printk(KERN_WARNING \
-		       "EISA: Cannot allocate resource for mainboard\n");
+		dev_warn(root->dev,
+		         "EISA: Cannot allocate resource for mainboard\n");
 		kfree(edev);
 		if (!root->force_probe)
 			return -EBUSY;
@@ -344,11 +344,11 @@ static int __init eisa_probe(struct eisa_root_device *root)
 		goto force_probe;
 	}
 
-	printk(KERN_INFO "EISA: Mainboard %s detected.\n", edev->id.sig);
+	dev_info(&edev->dev, "EISA: Mainboard %s detected\n", edev->id.sig);
 
 	if (eisa_register_device(edev)) {
-		printk(KERN_ERR "EISA: Failed to register %s\n",
-		       edev->id.sig);
+		dev_err(&edev->dev, "EISA: Failed to register %s\n",
+		        edev->id.sig);
 		eisa_release_resources(edev);
 		kfree(edev);
 	}
@@ -358,14 +358,15 @@ static int __init eisa_probe(struct eisa_root_device *root)
         for (c = 0, i = 1; i <= root->slots; i++) {
 		edev = kzalloc(sizeof(*edev), GFP_KERNEL);
 		if (!edev) {
-			printk(KERN_ERR "EISA: Out of memory for slot %d\n", i);
+			dev_err(root->dev, "EISA: Out of memory for slot %d\n",
+				i);
 			continue;
 		}
 
 		if (eisa_request_resources(root, edev, i)) {
-			printk(KERN_WARNING \
-			       "Cannot allocate resource for EISA slot %d\n",
-			       i);
+			dev_warn(root->dev,
+			         "Cannot allocate resource for EISA slot %d\n",
+			         i);
 			kfree(edev);
 			continue;
 		}
@@ -375,38 +376,30 @@ static int __init eisa_probe(struct eisa_root_device *root)
 			kfree(edev);
 			continue;
 		}
-		
-		printk(KERN_INFO "EISA: slot %d : %s detected",
-		       i, edev->id.sig);
-			
-		switch (edev->state) {
-		case EISA_CONFIG_ENABLED | EISA_CONFIG_FORCED:
-			printk(" (forced enabled)");
-			break;
-
-		case EISA_CONFIG_FORCED:
-			printk(" (forced disabled)");
-			break;
-
-		case 0:
-			printk(" (disabled)");
-			break;
-		}
-			
-		printk (".\n");
+
+		if (edev->state == (EISA_CONFIG_ENABLED | EISA_CONFIG_FORCED))
+			enabled_str = " (forced enabled)";
+		else if (edev->state == EISA_CONFIG_FORCED)
+			enabled_str = " (forced disabled)";
+		else if (edev->state == 0)
+			enabled_str = " (disabled)";
+		else
+			enabled_str = "";
+
+		dev_info(&edev->dev, "EISA: slot %d: %s detected%s\n", i,
+			 edev->id.sig, enabled_str);
 
 		c++;
 
 		if (eisa_register_device(edev)) {
-			printk(KERN_ERR "EISA: Failed to register %s\n",
-			       edev->id.sig);
+			dev_err(&edev->dev, "EISA: Failed to register %s\n",
+			        edev->id.sig);
 			eisa_release_resources(edev);
 			kfree(edev);
 		}
         }
 
-	printk(KERN_INFO "EISA: Detected %d card%s.\n", c, c == 1 ? "" : "s");
-
+	dev_info(root->dev, "EISA: Detected %d card%s\n", c, c == 1 ? "" : "s");
 	return 0;
 }
 
diff --git a/drivers/eisa/pci_eisa.c b/drivers/eisa/pci_eisa.c
index 6c3fca9..a333bf3 100644
--- a/drivers/eisa/pci_eisa.c
+++ b/drivers/eisa/pci_eisa.c
@@ -25,8 +25,7 @@ static int __init pci_eisa_init(struct pci_dev *pdev)
 	struct resource *res, *bus_res = NULL;
 
 	if ((rc = pci_enable_device (pdev))) {
-		printk (KERN_ERR "pci_eisa : Could not enable device %s\n",
-			pci_name(pdev));
+		dev_err(&pdev->dev, "Could not enable device\n");
 		return rc;
 	}
 
@@ -59,7 +58,7 @@ static int __init pci_eisa_init(struct pci_dev *pdev)
 	dev_set_drvdata(pci_eisa_root.dev, &pci_eisa_root);
 
 	if (eisa_root_register (&pci_eisa_root)) {
-		printk (KERN_ERR "pci_eisa : Could not register EISA root\n");
+		dev_err(&pdev->dev, "Could not register EISA root\n");
 		return -1;
 	}
 

commit 3a94edb7ba59d3ca30a3a54d8de628f1ccf004e4
Author: Bjorn Helgaas <bhelgaas@google.com>
Date:   Mon Apr 1 14:40:05 2013 -0600

    EISA: Log device resources in dmesg
    
    Note the resources consumed by EISA devices in dmesg, similar to what
    we already do for PCI and PNP devices.
    
    Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/eisa/eisa-bus.c b/drivers/eisa/eisa-bus.c
index 0b06df4..a6fbf98 100644
--- a/drivers/eisa/eisa-bus.c
+++ b/drivers/eisa/eisa-bus.c
@@ -288,6 +288,7 @@ static int __init eisa_request_resources(struct eisa_root_device *root,
 			edev->res[i].flags = IORESOURCE_BUSY;
 		}
 
+		dev_printk(KERN_DEBUG, &edev->dev, "%pR\n", &edev->res[i]);
 		if (request_resource(root->res, &edev->res[i]))
 			goto failed;
 	}

Re: [PATCH 0/2] eisa: fix eisa with PCI

[Bjorn Helgaas]

On Wed, Apr 3, 2013 at 1:48 PM, Matthew Whitehead <mwhitehe@redhat.com> wrote:

> It looks like it fixed /proc/ioports, but demsg is still (null). The boot log is attached.

Huh, I don't see the "(null)" in your patch4_boot.log.  Here's what I see:

[    1.816154] pci 0000:00:07.0: Probing EISA bus 0
[    1.820819] eisa 00:00: [io  0x0c80-0x0c83]
[    1.824092] eisa 00:00: EISA: Mainboard ALR01A4 detected
[    1.833195] eisa 00:04: [io  0x4000-0x40ff]
[    1.836097] eisa 00:04: [io  0x4400-0x44ff]
[    1.840084] eisa 00:04: [io  0x4800-0x48ff]
[    1.844084] eisa 00:04: [io  0x4c00-0x4cff]
[    1.848082] eisa 00:04: EISA: slot 4: TCM5093 detected
[    1.852947] eisa 00:06: [io  0x6000-0x60ff]
[    1.856092] eisa 00:06: [io  0x6400-0x64ff]
[    1.860082] eisa 00:06: [io  0x6800-0x68ff]
[    1.864083] eisa 00:06: [io  0x6c00-0x6cff]
[    1.868083] eisa 00:06: EISA: slot 6: HWP1940 detected (forced enabled)
[    1.873097] eisa 00:07: [io  0x7000-0x70ff]
[    1.876097] eisa 00:07: [io  0x7400-0x74ff]
[    1.880083] eisa 00:07: [io  0x7800-0x78ff]
[    1.884082] eisa 00:07: [io  0x7c00-0x7cff]
[    1.888090] eisa 00:07: EISA: slot 7: TCM5920 detected
[    1.892702] pci 0000:00:07.0: EISA: Detected 3 cards

This now matches exactly what you have in /proc/ioports, which is
good.  Previously there were a bunch of these:

[    1.796731]  (null): [io  0x1000-0x10ff]
[    1.800077]  (null): [io  0x1400-0x14ff]
...

and I couldn't figure out where they came from.  But those were an
artifact of setting up the resources before checking to see whether
there was a device there.  When we discovered there was no device
there, we discarded these resources, so it wasn't harmful, but dmesg
was still ugly.  Now that we check for a device first, we skip the
resources for empty slots 1, 2, 3, 5, and 8, which is much nicer.

Thanks for all your testing!

I put the bugfixes (Yinghai's patches) in my "for-linus" branch for
v3.9.  The other printk fixes and such don't fix any actual bugs, so
I'll put them in my "next" branch for merging into v3.10.

Bjorn