USB: xhci: Represent 64-bit addresses with one u64.
There are several xHCI data structures that use two 32-bit fields to
represent a 64-bit address. Since some architectures don't support 64-bit
PCI writes, the fields need to be written in two 32-bit writes. The xHCI
specification says that if a platform is incapable of generating 64-bit
writes, software must write the low 32-bits first, then the high 32-bits.
Hardware that supports 64-bit addressing will wait for the high 32-bit
write before reading the revised value, and hardware that only supports
32-bit writes will ignore the high 32-bit write.
Previous xHCI code represented 64-bit addresses with two u32 values. This
lead to buggy code that would write the 32-bits in the wrong order, or
forget to write the upper 32-bits. Change the two u32s to one u64 and
create a function call to write all 64-bit addresses in the proper order.
This new function could be modified in the future if all platforms support
64-bit writes.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index cde648a..60770c8 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -25,6 +25,7 @@
#include <linux/usb.h>
#include <linux/timer.h>
+#include <linux/kernel.h>
#include "../core/hcd.h"
/* Code sharing between pci-quirks and xhci hcd */
@@ -42,14 +43,6 @@
* xHCI register interface.
* This corresponds to the eXtensible Host Controller Interface (xHCI)
* Revision 0.95 specification
- *
- * Registers should always be accessed with double word or quad word accesses.
- *
- * Some xHCI implementations may support 64-bit address pointers. Registers
- * with 64-bit address pointers should be written to with dword accesses by
- * writing the low dword first (ptr[0]), then the high dword (ptr[1]) second.
- * xHCI implementations that do not support 64-bit address pointers will ignore
- * the high dword, and write order is irrelevant.
*/
/**
@@ -166,10 +159,10 @@
u32 reserved1;
u32 reserved2;
u32 dev_notification;
- u32 cmd_ring[2];
+ u64 cmd_ring;
/* rsvd: offset 0x20-2F */
u32 reserved3[4];
- u32 dcbaa_ptr[2];
+ u64 dcbaa_ptr;
u32 config_reg;
/* rsvd: offset 0x3C-3FF */
u32 reserved4[241];
@@ -254,7 +247,7 @@
#define CMD_RING_RUNNING (1 << 3)
/* bits 4:5 reserved and should be preserved */
/* Command Ring pointer - bit mask for the lower 32 bits. */
-#define CMD_RING_ADDR_MASK (0xffffffc0)
+#define CMD_RING_RSVD_BITS (0x3f)
/* CONFIG - Configure Register - config_reg bitmasks */
/* bits 0:7 - maximum number of device slots enabled (NumSlotsEn) */
@@ -382,8 +375,8 @@
u32 irq_control;
u32 erst_size;
u32 rsvd;
- u32 erst_base[2];
- u32 erst_dequeue[2];
+ u64 erst_base;
+ u64 erst_dequeue;
};
/* irq_pending bitmasks */
@@ -538,7 +531,7 @@
struct xhci_ep_ctx {
u32 ep_info;
u32 ep_info2;
- u32 deq[2];
+ u64 deq;
u32 tx_info;
/* offset 0x14 - 0x1f reserved for HC internal use */
u32 reserved[3];
@@ -641,7 +634,7 @@
*/
struct xhci_device_context_array {
/* 64-bit device addresses; we only write 32-bit addresses */
- u32 dev_context_ptrs[2*MAX_HC_SLOTS];
+ u64 dev_context_ptrs[MAX_HC_SLOTS];
/* private xHCD pointers */
dma_addr_t dma;
};
@@ -654,7 +647,7 @@
struct xhci_stream_ctx {
/* 64-bit stream ring address, cycle state, and stream type */
- u32 stream_ring[2];
+ u64 stream_ring;
/* offset 0x14 - 0x1f reserved for HC internal use */
u32 reserved[2];
};
@@ -662,7 +655,7 @@
struct xhci_transfer_event {
/* 64-bit buffer address, or immediate data */
- u32 buffer[2];
+ u64 buffer;
u32 transfer_len;
/* This field is interpreted differently based on the type of TRB */
u32 flags;
@@ -744,7 +737,7 @@
struct xhci_link_trb {
/* 64-bit segment pointer*/
- u32 segment_ptr[2];
+ u64 segment_ptr;
u32 intr_target;
u32 control;
};
@@ -755,7 +748,7 @@
/* Command completion event TRB */
struct xhci_event_cmd {
/* Pointer to command TRB, or the value passed by the event data trb */
- u32 cmd_trb[2];
+ u64 cmd_trb;
u32 status;
u32 flags;
};
@@ -943,7 +936,7 @@
struct xhci_erst_entry {
/* 64-bit event ring segment address */
- u32 seg_addr[2];
+ u64 seg_addr;
u32 seg_size;
/* Set to zero */
u32 rsvd;
@@ -1079,6 +1072,38 @@
writel(val, regs);
}
+/*
+ * Registers should always be accessed with double word or quad word accesses.
+ *
+ * Some xHCI implementations may support 64-bit address pointers. Registers
+ * with 64-bit address pointers should be written to with dword accesses by
+ * writing the low dword first (ptr[0]), then the high dword (ptr[1]) second.
+ * xHCI implementations that do not support 64-bit address pointers will ignore
+ * the high dword, and write order is irrelevant.
+ */
+static inline u64 xhci_read_64(const struct xhci_hcd *xhci,
+ __u64 __iomem *regs)
+{
+ __u32 __iomem *ptr = (__u32 __iomem *) regs;
+ u64 val_lo = readl(ptr);
+ u64 val_hi = readl(ptr + 1);
+ return val_lo + (val_hi << 32);
+}
+static inline void xhci_write_64(struct xhci_hcd *xhci,
+ const u64 val, __u64 __iomem *regs)
+{
+ __u32 __iomem *ptr = (__u32 __iomem *) regs;
+ u32 val_lo = lower_32_bits(val);
+ u32 val_hi = upper_32_bits(val);
+
+ if (!in_interrupt())
+ xhci_dbg(xhci,
+ "`MEM_WRITE_DWORD(3'b000, 64'h%p, 64'h%0lx, 4'hf);\n",
+ regs, (long unsigned int) val);
+ writel(val_lo, ptr);
+ writel(val_hi, ptr + 1);
+}
+
/* xHCI debugging */
void xhci_print_ir_set(struct xhci_hcd *xhci, struct xhci_intr_reg *ir_set, int set_num);
void xhci_print_registers(struct xhci_hcd *xhci);