[RFC PATCH v2 01/22] xhci: fix event ring segment table related masks and variables in header

[Wesley Cheng <quic_wcheng@quicinc.com>]

From: Mathias Nyman <mathias.nyman@linux.intel.com>

xHC controller can supports up to 1024 interrupters.
To fit these change the max_interrupters varable from u8 to u16.

Add a separate mask for the reserve and preserve bits [5:0] in the erst
base register and use it instead of the ERST_PRT_MASK.
ERSR_PTR_MASK [3:0] is intended for masking bits in the
event ring dequeue pointer register.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 4 ++--
 drivers/usb/host/xhci.h     | 5 ++++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 81ca2bc1f0be..679befa97c7a 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2529,8 +2529,8 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 			"// Set ERST base address for ir_set 0 = 0x%llx",
 			(unsigned long long)xhci->erst.erst_dma_addr);
 	val_64 = xhci_read_64(xhci, &xhci->ir_set->erst_base);
-	val_64 &= ERST_PTR_MASK;
-	val_64 |= (xhci->erst.erst_dma_addr & (u64) ~ERST_PTR_MASK);
+	val_64 &= ERST_BASE_RSVDP;
+	val_64 |= (xhci->erst.erst_dma_addr & (u64) ~ERST_BASE_RSVDP);
 	xhci_write_64(xhci, val_64, &xhci->ir_set->erst_base);
 
 	/* Set the event ring dequeue address */
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index c9f06c5e4e9d..e1362e0c50e1 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -513,6 +513,9 @@ struct xhci_intr_reg {
 /* Preserve bits 16:31 of erst_size */
 #define	ERST_SIZE_MASK		(0xffff << 16)
 
+/* erst_base bitmasks */
+#define ERST_BASE_RSVDP		(0x3f)
+
 /* erst_dequeue bitmasks */
 /* Dequeue ERST Segment Index (DESI) - Segment number (or alias)
  * where the current dequeue pointer lies.  This is an optional HW hint.
@@ -1773,7 +1776,7 @@ struct xhci_hcd {
 	u8		sbrn;
 	u16		hci_version;
 	u8		max_slots;
-	u8		max_interrupters;
+	u16		max_interrupters;
 	u8		max_ports;
 	u8		isoc_threshold;
 	/* imod_interval in ns (I * 250ns) */