arm64/boot: Disable trapping of PMZR_EL0 writes to EL2grafted

__init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2.
PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in
HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host
traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The
kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU
driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a
write from EL0 reaches the trap and takes the host down without a panic
message.

Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already
does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9
bits.

Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9")
Cc: stable@vger.kernel.org
Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 104 insertions, 0 deletions

diff --git a/include/video/udlfb.h b/include/video/udlfb.h
new file mode 100644
index 000000000..ab34790d5
--- /dev/null
+++ b/include/video/udlfb.h
@@ -0,0 +1,104 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef UDLFB_H
+#define UDLFB_H
+
+/*
+ * TODO: Propose standard fb.h ioctl for reporting damage,
+ * using _IOWR() and one of the existing area structs from fb.h
+ * Consider these ioctls deprecated, but they're still used by the
+ * DisplayLink X server as yet - need both to be modified in tandem
+ * when new ioctl(s) are ready.
+ */
+#define DLFB_IOCTL_RETURN_EDID	 0xAD
+#define DLFB_IOCTL_REPORT_DAMAGE 0xAA
+struct dloarea {
+	int x, y;
+	int w, h;
+	int x2, y2;
+};
+
+struct urb_node {
+	struct list_head entry;
+	struct dlfb_data *dlfb;
+	struct urb *urb;
+};
+
+struct urb_list {
+	struct list_head list;
+	spinlock_t lock;
+	struct semaphore limit_sem;
+	int available;
+	int count;
+	size_t size;
+};
+
+struct dlfb_data {
+	struct usb_device *udev;
+	struct fb_info *info;
+	struct urb_list urbs;
+	char *backing_buffer;
+	int fb_count;
+	bool virtualized; /* true when physical usb device not present */
+	atomic_t usb_active; /* 0 = update virtual buffer, but no usb traffic */
+	atomic_t lost_pixels; /* 1 = a render op failed. Need screen refresh */
+	char *edid; /* null until we read edid from hw or get from sysfs */
+	size_t edid_size;
+	int sku_pixel_limit;
+	int base16;
+	int base8;
+	u32 pseudo_palette[256];
+	int blank_mode; /*one of FB_BLANK_ */
+	struct mutex render_mutex;
+	int damage_x;
+	int damage_y;
+	int damage_x2;
+	int damage_y2;
+	spinlock_t damage_lock;
+	struct work_struct damage_work;
+	struct fb_ops ops;
+	atomic_t mmap_count;
+	/* blit-only rendering path metrics, exposed through sysfs */
+	atomic_t bytes_rendered; /* raw pixel-bytes driver asked to render */
+	atomic_t bytes_identical; /* saved effort with backbuffer comparison */
+	atomic_t bytes_sent; /* to usb, after compression including overhead */
+	atomic_t cpu_kcycles_used; /* transpired during pixel processing */
+	struct fb_var_screeninfo current_mode;
+	struct list_head deferred_free;
+};
+
+#define NR_USB_REQUEST_I2C_SUB_IO 0x02
+#define NR_USB_REQUEST_CHANNEL 0x12
+
+/* -BULK_SIZE as per usb-skeleton. Can we get full page and avoid overhead? */
+#define BULK_SIZE 512
+#define MAX_TRANSFER (PAGE_SIZE*16 - BULK_SIZE)
+#define WRITES_IN_FLIGHT (4)
+
+#define MAX_VENDOR_DESCRIPTOR_SIZE 256
+
+#define GET_URB_TIMEOUT	HZ
+#define FREE_URB_TIMEOUT (HZ*2)
+
+#define BPP                     2
+#define MAX_CMD_PIXELS		255
+
+#define RLX_HEADER_BYTES	7
+#define MIN_RLX_PIX_BYTES       4
+#define MIN_RLX_CMD_BYTES	(RLX_HEADER_BYTES + MIN_RLX_PIX_BYTES)
+
+#define RLE_HEADER_BYTES	6
+#define MIN_RLE_PIX_BYTES	3
+#define MIN_RLE_CMD_BYTES	(RLE_HEADER_BYTES + MIN_RLE_PIX_BYTES)
+
+#define RAW_HEADER_BYTES	6
+#define MIN_RAW_PIX_BYTES	2
+#define MIN_RAW_CMD_BYTES	(RAW_HEADER_BYTES + MIN_RAW_PIX_BYTES)
+
+#define DL_DEFIO_WRITE_DELAY    msecs_to_jiffies(HZ <= 300 ? 4 : 10) /* optimal value for 720p video */
+#define DL_DEFIO_WRITE_DISABLE  (HZ*60) /* "disable" with long delay */
+
+/* remove these once align.h patch is taken into kernel */
+#define DL_ALIGN_UP(x, a) ALIGN(x, a)
+#define DL_ALIGN_DOWN(x, a) ALIGN_DOWN(x, a)
+
+#endif