[PATCH AUTOSEL 5.2 43/94] r8152: Set memory to all 0xFFs on failed reg reads

[PATCH AUTOSEL 5.2 43/94] r8152: Set memory to all 0xFFs on failed reg reads

[Sasha Levin]

From: Prashant Malani <pmalani@chromium.org>

[ Upstream commit f53a7ad189594a112167efaf17ea8d0242b5ac00 ]

get_registers() blindly copies the memory written to by the
usb_control_msg() call even if the underlying urb failed.

This could lead to junk register values being read by the driver, since
some indirect callers of get_registers() ignore the return values. One
example is:
  ocp_read_dword() ignores the return value of generic_ocp_read(), which
  calls get_registers().

So, emulate PCI "Master Abort" behavior by setting the buffer to all
0xFFs when usb_control_msg() fails.

This patch is copied from the r8152 driver (v2.12.0) published by
Realtek (www.realtek.com).

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Acked-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/usb/r8152.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index e0dcb681cfe5a..7542afba019bb 100644
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -787,8 +787,11 @@ int get_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data)
 	ret = usb_control_msg(tp->udev, usb_rcvctrlpipe(tp->udev, 0),
 			      RTL8152_REQ_GET_REGS, RTL8152_REQT_READ,
 			      value, index, tmp, size, 500);
+	if (ret < 0)
+		memset(data, 0xff, size);
+	else
+		memcpy(data, tmp, size);
 
-	memcpy(data, tmp, size);
 	kfree(tmp);
 
 	return ret;
-- 
2.20.1

[PATCH AUTOSEL 5.2 64/94] usb: host: xhci-tegra: Set DMA mask correctly

[Sasha Levin]

From: Nagarjuna Kristam <nkristam@nvidia.com>

[ Upstream commit 993cc8753453fccfe060a535bbe21fcf1001b626 ]

The Falcon microcontroller that runs the XUSB firmware and which is
responsible for exposing the XHCI interface can address only 40 bits of
memory. Typically that's not a problem because Tegra devices don't have
enough system memory to exceed those 40 bits.

However, if the ARM SMMU is enable on Tegra186 and later, the addresses
passed to the XUSB controller can be anywhere in the 48-bit IOV address
space of the ARM SMMU. Since the DMA/IOMMU API starts allocating from
the top of the IOVA space, the Falcon microcontroller is not able to
load the firmware successfully.

Fix this by setting the DMA mask to 40 bits, which will force the DMA
API to map the buffer for the firmware to an IOVA that is addressable by
the Falcon.

Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/1566989697-13049-1-git-send-email-nkristam@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/host/xhci-tegra.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index 294158113d62c..77142f9bf26ae 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -1217,6 +1217,16 @@ static int tegra_xusb_probe(struct platform_device *pdev)
 
 	tegra_xusb_config(tegra, regs);
 
+	/*
+	 * The XUSB Falcon microcontroller can only address 40 bits, so set
+	 * the DMA mask accordingly.
+	 */
+	err = dma_set_mask_and_coherent(tegra->dev, DMA_BIT_MASK(40));
+	if (err < 0) {
+		dev_err(&pdev->dev, "failed to set DMA mask: %d\n", err);
+		goto put_rpm;
+	}
+
 	err = tegra_xusb_load_firmware(tegra);
 	if (err < 0) {
 		dev_err(&pdev->dev, "failed to load firmware: %d\n", err);
-- 
2.20.1