bcm27xx: add linux 5.4 support

Tested on bcm2710 (Raspberry Pi 3B).

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.4/950-0257-drm-vc4-handle-the-case-where-there-are-no-available.patch b/target/linux/bcm27xx/patches-5.4/950-0257-drm-vc4-handle-the-case-where-there-are-no-available.patch
new file mode 100644
index 0000000000..72b205c2e4
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.4/950-0257-drm-vc4-handle-the-case-where-there-are-no-available.patch
@@ -0,0 +1,67 @@
+From 1fbbd377bd1c6b4e3342d03091f19089ccb7fcbe Mon Sep 17 00:00:00 2001
+From: Jonathan Bell <jonathan@raspberrypi.org>
+Date: Tue, 28 May 2019 13:56:06 +0100
+Subject: [PATCH] drm: vc4: handle the case where there are no
+ available displays
+
+It's reasonable for the firmware to return zero as the number of
+attached displays. Handle this case as otherwise drm thinks that
+the DSI panel is attached, which is nonsense.
+
+Signed-off-by: Jonathan Bell <jonathan@raspberrypi.org>
+---
+ drivers/gpu/drm/vc4/vc4_firmware_kms.c | 32 +++++++++++++++-----------
+ 1 file changed, 18 insertions(+), 14 deletions(-)
+
+--- a/drivers/gpu/drm/vc4/vc4_firmware_kms.c
++++ b/drivers/gpu/drm/vc4/vc4_firmware_kms.c
+@@ -1303,13 +1303,13 @@ static int vc4_fkms_bind(struct device *
+ 				    RPI_FIRMWARE_FRAMEBUFFER_GET_NUM_DISPLAYS,
+ 				    &num_displays, sizeof(u32));
+ 
+-	/* If we fail to get the number of displays, or it returns 0, then
++	/* If we fail to get the number of displays, then
+ 	 * assume old firmware that doesn't have the mailbox call, so just
+ 	 * set one display
+ 	 */
+-	if (ret || num_displays == 0) {
++	if (ret) {
+ 		num_displays = 1;
+-		DRM_WARN("Unable to determine number of displays's. Assuming 1\n");
++		DRM_WARN("Unable to determine number of displays - assuming 1\n");
+ 		ret = 0;
+ 	}
+ 
+@@ -1338,17 +1338,21 @@ static int vc4_fkms_bind(struct device *
+ 				  display_num);
+ 	}
+ 
+-	/* Map the SMI interrupt reg */
+-	crtc_list[0]->regs = vc4_ioremap_regs(pdev, 0);
+-	if (IS_ERR(crtc_list[0]->regs))
+-		DRM_ERROR("Oh dear, failed to map registers\n");
+-
+-	writel(0, crtc_list[0]->regs + SMICS);
+-	ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
+-			       vc4_crtc_irq_handler, 0, "vc4 firmware kms",
+-			       crtc_list);
+-	if (ret)
+-		DRM_ERROR("Oh dear, failed to register IRQ\n");
++	if (num_displays > 0) {
++		/* Map the SMI interrupt reg */
++		crtc_list[0]->regs = vc4_ioremap_regs(pdev, 0);
++		if (IS_ERR(crtc_list[0]->regs))
++			DRM_ERROR("Oh dear, failed to map registers\n");
++
++		writel(0, crtc_list[0]->regs + SMICS);
++		ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
++				       vc4_crtc_irq_handler, 0,
++				       "vc4 firmware kms", crtc_list);
++		if (ret)
++			DRM_ERROR("Oh dear, failed to register IRQ\n");
++	} else {
++		DRM_WARN("No displays found. Consider forcing hotplug if HDMI is attached\n");
++	}
+ 
+ 	platform_set_drvdata(pdev, crtc_list);
+