pciehp: Let user control LED status

This patch adds a new function to set PCI domain specific options as devices are added. The usage included in this patch is for LED indicator control in VMD domains, but may be extended in the future as new domain specific options are required.

PCIe LED Slot Control in a VMD domain is repurposed to a non-standard implementation. As such, all devices in a VMD domain will be flagged so pciehp does not attempt to use LED indicators. This user_led flag has pciehp provide a different sysfs entry for user exclusive control over the domain's slot indicators.

In order to determine if a bus is within a PCI domain, the patch appends a bool to the pci_sysdata structure that the VMD driver sets during initialization.

Requested-by Kapil Karkra <[email protected]>

Tested-by Artur Paszkiewicz <[email protected]>

Signed-off-by Keith Busch <[email protected]>

---

No change from previous version of this patch; just part of the series.

 arch/x86/include/asm/pci.h | 14 ++++++++++++++
 arch/x86/pci/common.c      |  7 +++++++
 arch/x86/pci/vmd.c         |  1 +
 3 files changed, 22 insertions(+)

arch/x86/include/asm/pci.h +14 -0

index 9ab7507..1411dbe 100644
@@ -23,6 +23,9 @@ struct pci_sysdata {
 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
 	void		*fwnode;	/* IRQ domain for MSI assignment */
 #endif
+#if IS_ENABLED(CONFIG_VMD)
+	bool vmd_domain;		/* True if in Intel VMD domain */
+#endif
 };
 
 extern int pci_routeirq;

@@ -56,6 +59,17 @@ static inline void *_pci_root_bus_fwnode(struct pci_bus *bus)
 #define pci_root_bus_fwnode	_pci_root_bus_fwnode
 #endif
 
+static inline bool is_vmd(struct pci_bus *bus)
+{
+#if IS_ENABLED(CONFIG_VMD)
+	struct pci_sysdata *sd = bus->sysdata;
+
+	return sd->vmd_domain;
+#else
+	return false;
+#endif
+}
+
 /* Can be used to override the logic in pci_scan_bus for skipping
    already-configured bus numbers - to be used for buggy BIOSes
    or architectures with incomplete PCI setup by the loader */

arch/x86/pci/common.c +7 -0

index 7b6a9d1..ccf696c 100644
@@ -677,6 +677,12 @@ static void set_dma_domain_ops(struct pci_dev *pdev)
 static void set_dma_domain_ops(struct pci_dev *pdev) {}
 #endif
 
+static void set_dev_domain_options(struct pci_dev *pdev)
+{
+	if (is_vmd(pdev->bus))
+		pdev->user_leds = 1;
+}
+
 int pcibios_add_device(struct pci_dev *dev)
 {
 	struct setup_data *data;

@@ -707,6 +713,7 @@ int pcibios_add_device(struct pci_dev *dev)
 		iounmap(data);
 	}
 	set_dma_domain_ops(dev);
+	set_dev_domain_options(dev);
 	return 0;
 }
 

arch/x86/pci/vmd.c +1 -0

index b814ca6..a021b7b 100644
@@ -596,6 +596,7 @@ static int vmd_enable_domain(struct vmd_dev *vmd)
 		.parent = res,
 	};
 
+	sd->vmd_domain = true;
 	sd->domain = vmd_find_free_domain();
 	if (sd->domain < 0)
 		return sd->domain;

Signature · 6 lines

2.7.2

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I made the necessary changes to match the renaming I did in the first patch, and I also used plain old "#ifdef" instead of "#if IS_ENABLED" since the rest of the file uses the former style. If there's a reason to switch, we should change the whole file in a separate patch so we can explain the rationale.

Quoted 5 lines · Bjorn Helgaas

I made the necessary changes to match the renaming I did in the first patch, and I also used plain old "#ifdef" instead of "#if IS_ENABLED" since the rest of the file uses the former style. If there's a reason to switch, we should change the whole file in a separate patch so we can explain the rationale.

The check was "IS_ENABLED" because VMD can be a loadable module, which fails the ifdef check. I see Fengguang 0'dayed it using the module configuration option. I can send you a fix based on your pci/hotplug branch, or revert and apply the original patch if you prefer.

BTW, you had asked me not to split a series when incremental fixes touched a single patch. I didn't resend the whole series here, and while you got the right patches, I apologize for making it more difficult to find.

BTW, the "Volume Management Device Driver" config item appears by itself in the top-level menuconfig menu. That seems a little ... presumptuous; is it what you intended?

This patch adds a new function to set PCI domain specific options as devices are added. The usage included in this patch is for LED indicator control in VMD domains, but may be extended in the future as new domain specific options are required.

PCIe LED Slot Control in a VMD domain is repurposed to a non-standard implementation. As such, all devices in a VMD domain will be flagged so pciehp does not attempt to use LED indicators. This user_led flag has pciehp provide a different sysfs entry for user exclusive control over the domain's slot indicators.

In order to determine if a bus is within a PCI domain, the patch appends a bool to the pci_sysdata structure that the VMD driver sets during initialization.

 arch/x86/include/asm/pci.h | 14 ++++++++++++++
 arch/x86/pci/common.c      |  7 +++++++
 arch/x86/pci/vmd.c         |  1 +
 3 files changed, 22 insertions(+)

arch/x86/include/asm/pci.h +14 -0

index 9ab7507..1411dbe 100644
@@ -23,6 +23,9 @@ struct pci_sysdata {
 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
 	void		*fwnode;	/* IRQ domain for MSI assignment */
 #endif
+#if IS_ENABLED(CONFIG_VMD)
+	bool vmd_domain;		/* True if in Intel VMD domain */
+#endif
 };
 
 extern int pci_routeirq;

@@ -56,6 +59,17 @@ static inline void *_pci_root_bus_fwnode(struct pci_bus *bus)
 #define pci_root_bus_fwnode	_pci_root_bus_fwnode
 #endif
 
+static inline bool is_vmd(struct pci_bus *bus)
+{
+#if IS_ENABLED(CONFIG_VMD)
+	struct pci_sysdata *sd = bus->sysdata;
+
+	return sd->vmd_domain;
+#else
+	return false;
+#endif
+}
+
 /* Can be used to override the logic in pci_scan_bus for skipping
    already-configured bus numbers - to be used for buggy BIOSes
    or architectures with incomplete PCI setup by the loader */

arch/x86/pci/common.c +7 -0

index 7b6a9d1..ccf696c 100644
@@ -677,6 +677,12 @@ static void set_dma_domain_ops(struct pci_dev *pdev)
 static void set_dma_domain_ops(struct pci_dev *pdev) {}
 #endif
 
+static void set_dev_domain_options(struct pci_dev *pdev)
+{
+	if (is_vmd(pdev->bus))
+		pdev->user_leds = 1;
+}
+
 int pcibios_add_device(struct pci_dev *dev)
 {
 	struct setup_data *data;

@@ -707,6 +713,7 @@ int pcibios_add_device(struct pci_dev *dev)
 		iounmap(data);
 	}
 	set_dma_domain_ops(dev);
+	set_dev_domain_options(dev);
 	return 0;
 }
 

arch/x86/pci/vmd.c +1 -0

index b814ca6..a021b7b 100644
@@ -596,6 +596,7 @@ static int vmd_enable_domain(struct vmd_dev *vmd)
 		.parent = res,
 	};
 
+	sd->vmd_domain = true;
 	sd->domain = vmd_find_free_domain();
 	if (sd->domain < 0)
 		return sd->domain;

Signature · 1 line

2.7.2