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From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
To:     linux-pci@vger.kernel.org
Cc:     Jiaxun Yang <jiaxun.yang@flygoat.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Rob Herring <robh+dt@kernel.org>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Huacai Chen <chenhc@lemote.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Andrew Murray <amurray@thegoodpenguin.co.uk>,
        Paul Burton <paulburton@kernel.org>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mips@vger.kernel.org
Subject: [PATCH v5 1/6] PCI: OF: Don't remap iospace on unsupported platform
Date:   Fri, 24 Apr 2020 21:08:32 +0800
Message-Id: <20200424130847.328584-2-jiaxun.yang@flygoat.com>
In-Reply-To: <20200424130847.328584-1-jiaxun.yang@flygoat.com>
References: <20200424130847.328584-1-jiaxun.yang@flygoat.com>
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There are some platforms that don't support I/O space remapping
like MIPS. However, our PCI code will try to remap iospace
unconditionally and reject io resources on these platforms.

So we should remove I/O space remapping check and use a range
check instead on these platforms.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
--
v4: Fix a typo in commit message.
v5: Commit message massage
---
 drivers/pci/of.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index 81ceeaa6f1d5..36e8761b66c6 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -547,12 +547,21 @@ int pci_parse_request_of_pci_ranges(struct device *dev,
 
 		switch (resource_type(res)) {
 		case IORESOURCE_IO:
+#if defined(PCI_IOBASE) && defined(CONFIG_MMU)
 			err = devm_pci_remap_iospace(dev, res, iobase);
 			if (err) {
 				dev_warn(dev, "error %d: failed to map resource %pR\n",
 					 err, res);
 				resource_list_destroy_entry(win);
 			}
+#else
+			/* Simply check if IO is inside the range */
+			if (res->end > IO_SPACE_LIMIT) {
+				dev_warn(dev, "resource %pR out of the I/O range\n",
+					res);
+				resource_list_destroy_entry(win);
+			}
+#endif
 			break;
 		case IORESOURCE_MEM:
 			res_valid |= !(res->flags & IORESOURCE_PREFETCH);
-- 
2.26.0.rc2