Patch "PCI: thunder-pem: Fix legacy firmware PEM-specific resources" has been added to the 4.10-stable tree

This is a note to let you know that I've just added the patch titled

PCI: thunder-pem: Fix legacy firmware PEM-specific resources

to the 4.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
pci-thunder-pem-fix-legacy-firmware-pem-specific-resources.patch
and it can be found in the queue-4.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Tomasz Nowicki <[email protected]>
Date: Fri, 31 Mar 2017 17:06:44 +0200
Subject: PCI: thunder-pem: Fix legacy firmware PEM-specific resources

From: Tomasz Nowicki <[email protected]>

commit feb199ebef488a9f2c3550fb10524f3dac9d8abe upstream.

SZ_16M PEM resource size includes PEM-specific register and its children resources. Reservation of the whole SZ_16M range leads to child device driver failure when pcieport driver is requesting resources:

pcieport 0004:1f:00.0: can't enable device: BAR 0 [mem 0x87e0c0f00000-0x87e0c0ffffff 64bit] not claimed

So we cannot reserve full 16M here and instead we want to reserve PEM-specific register only which is SZ_64K.

At the end increase PEM resource to SZ_16M since this is what thunder_pem_init() call expects for proper initialization.

---
 drivers/pci/host/pci-thunder-pem.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

@@ -360,7 +360,6 @@ static void thunder_pem_legacy_fw(struct
 	index -= node * PEM_MAX_DOM_IN_NODE;
 	res_pem->start = PEM_RES_BASE | FIELD_PREP(PEM_NODE_MASK, node) |
 					FIELD_PREP(PEM_INDX_MASK, index);
-	res_pem->end = res_pem->start + SZ_16M - 1;
 	res_pem->flags = IORESOURCE_MEM;
 }
 

@@ -384,8 +383,15 @@ static int thunder_pem_acpi_init(struct
 	 */
 	if (ret) {
 		thunder_pem_legacy_fw(root, res_pem);
-		/* Reserve PEM-specific resources and PCI configuration space */
+		/*
+		 * Reserve 64K size PEM specific resources. The full 16M range
+		 * size is required for thunder_pem_init() call.
+		 */
+		res_pem->end = res_pem->start + SZ_64K - 1;
 		thunder_pem_reserve_range(dev, root->segment, res_pem);
+		res_pem->end = res_pem->start + SZ_16M - 1;
+
+		/* Reserve PCI configuration space as well. */
 		thunder_pem_reserve_range(dev, root->segment, &cfg->res);
 	}
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.10/pci-thunder-pem-add-legacy-firmware-support-for-cavium-thunderx-host-controller.patch queue-4.10/pci-thunder-pem-fix-legacy-firmware-pem-specific-resources.patch