[PATCH v2 1/2] PCI: xgene: Revert "PCI: xgene: Use inbound resources for setup"

[PATCH v2 1/2] PCI: xgene: Revert "PCI: xgene: Use inbound resources for setup"

[Marc Zyngier]

Commit 6dce5aa59e0b ("PCI: xgene: Use inbound resources for setup")
killed PCIe on my XGene-1 box (a Mustang board). The machine itself
is still alive, but half of its storage (over NVMe) is gone, and the
NVMe driver just times out.

Note that this machine boots with a device tree provided by the
UEFI firmware (2016 vintage), which could well be non conformant
with the spec, hence the breakage.

With the patch reverted, the box boots 5.17-rc8 with flying colors.

Cc: Rob Herring <robh@kernel.org>
Cc: Toan Le <toan@os.amperecomputing.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Krzysztof Wilczyński <kw@linux.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Stéphane Graber <stgraber@ubuntu.com>
Cc: dann frazier <dann.frazier@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Fixes: 6dce5aa59e0b ("PCI: xgene: Use inbound resources for setup")
Link: https://lore.kernel.org/all/Yf2wTLjmcRj+AbDv@xps13.dannf
---
 drivers/pci/controller/pci-xgene.c | 33 ++++++++++++++++++++----------
 1 file changed, 22 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/controller/pci-xgene.c b/drivers/pci/controller/pci-xgene.c
index 0d5acbfc7143..aa41ceaf031f 100644
--- a/drivers/pci/controller/pci-xgene.c
+++ b/drivers/pci/controller/pci-xgene.c
@@ -479,28 +479,27 @@ static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size)
 }
 
 static void xgene_pcie_setup_ib_reg(struct xgene_pcie *port,
-				    struct resource_entry *entry,
-				    u8 *ib_reg_mask)
+				    struct of_pci_range *range, u8 *ib_reg_mask)
 {
 	void __iomem *cfg_base = port->cfg_base;
 	struct device *dev = port->dev;
 	void __iomem *bar_addr;
 	u32 pim_reg;
-	u64 cpu_addr = entry->res->start;
-	u64 pci_addr = cpu_addr - entry->offset;
-	u64 size = resource_size(entry->res);
+	u64 cpu_addr = range->cpu_addr;
+	u64 pci_addr = range->pci_addr;
+	u64 size = range->size;
 	u64 mask = ~(size - 1) | EN_REG;
 	u32 flags = PCI_BASE_ADDRESS_MEM_TYPE_64;
 	u32 bar_low;
 	int region;
 
-	region = xgene_pcie_select_ib_reg(ib_reg_mask, size);
+	region = xgene_pcie_select_ib_reg(ib_reg_mask, range->size);
 	if (region < 0) {
 		dev_warn(dev, "invalid pcie dma-range config\n");
 		return;
 	}
 
-	if (entry->res->flags & IORESOURCE_PREFETCH)
+	if (range->flags & IORESOURCE_PREFETCH)
 		flags |= PCI_BASE_ADDRESS_MEM_PREFETCH;
 
 	bar_low = pcie_bar_low_val((u32)cpu_addr, flags);
@@ -531,13 +530,25 @@ static void xgene_pcie_setup_ib_reg(struct xgene_pcie *port,
 
 static int xgene_pcie_parse_map_dma_ranges(struct xgene_pcie *port)
 {
-	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(port);
-	struct resource_entry *entry;
+	struct device_node *np = port->node;
+	struct of_pci_range range;
+	struct of_pci_range_parser parser;
+	struct device *dev = port->dev;
 	u8 ib_reg_mask = 0;
 
-	resource_list_for_each_entry(entry, &bridge->dma_ranges)
-		xgene_pcie_setup_ib_reg(port, entry, &ib_reg_mask);
+	if (of_pci_dma_range_parser_init(&parser, np)) {
+		dev_err(dev, "missing dma-ranges property\n");
+		return -EINVAL;
+	}
+
+	/* Get the dma-ranges from DT */
+	for_each_of_pci_range(&parser, &range) {
+		u64 end = range.cpu_addr + range.size - 1;
 
+		dev_dbg(dev, "0x%08x 0x%016llx..0x%016llx -> 0x%016llx\n",
+			range.flags, range.cpu_addr, end, range.pci_addr);
+		xgene_pcie_setup_ib_reg(port, &range, &ib_reg_mask);
+	}
 	return 0;
 }
 
-- 
2.34.1

[PATCH v2 2/2] PCI: xgene: Revert "PCI: xgene: Fix IB window setup"

[Marc Zyngier]

Commit c7a75d07827a ("PCI: xgene: Fix IB window setup") tried to
fix the damages that 6dce5aa59e0b ("PCI: xgene: Use inbound resources
for setup") caused, but actually didn't improve anything for some
plarforms (at least Mustang and m400 are still broken).

Given that 6dce5aa59e0b has been reverted, revert this patch as well,
restoring the PCIe support on XGene to its pre-5.5, working state.

Cc: Rob Herring <robh@kernel.org>
Cc: Toan Le <toan@os.amperecomputing.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Krzysztof Wilczyński <kw@linux.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Stéphane Graber <stgraber@ubuntu.com>
Cc: dann frazier <dann.frazier@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Fixes: c7a75d07827a ("PCI: xgene: Fix IB window setup")
Link: https://lore.kernel.org/r/YjN8pT5e6/8cRohQ@xps13.dannf
---
 drivers/pci/controller/pci-xgene.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pci-xgene.c b/drivers/pci/controller/pci-xgene.c
index aa41ceaf031f..7c763d820c52 100644
--- a/drivers/pci/controller/pci-xgene.c
+++ b/drivers/pci/controller/pci-xgene.c
@@ -465,7 +465,7 @@ static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size)
 		return 1;
 	}
 
-	if ((size > SZ_1K) && (size < SZ_4G) && !(*ib_reg_mask & (1 << 0))) {
+	if ((size > SZ_1K) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 0))) {
 		*ib_reg_mask |= (1 << 0);
 		return 0;
 	}
-- 
2.34.1