Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / ipxe / src / interface / efi / efi_timer.c

diff --git a/qemu/roms/ipxe/src/interface/efi/efi_timer.c b/qemu/roms/ipxe/src/interface/efi/efi_timer.c
new file mode 100644 (file)
index 0000000..7a1ff78
--- /dev/null
+++ b/qemu/roms/ipxe/src/interface/efi/efi_timer.c
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <string.h>
+#include <errno.h>
+#include <limits.h>
+#include <assert.h>
+#include <unistd.h>
+#include <ipxe/timer.h>
+#include <ipxe/efi/efi.h>
+#include <ipxe/efi/Protocol/Cpu.h>
+
+/** @file
+ *
+ * iPXE timer API for EFI
+ *
+ */
+
+/** Scale factor to apply to CPU timer 0
+ *
+ * The timer is scaled down in order to ensure that reasonable values
+ * for "number of ticks" don't exceed the size of an unsigned long.
+ */
+#define EFI_TIMER0_SHIFT 12
+
+/** Calibration time */
+#define EFI_CALIBRATE_DELAY_MS 1
+
+/** CPU protocol */
+static EFI_CPU_ARCH_PROTOCOL *cpu_arch;
+EFI_REQUIRE_PROTOCOL ( EFI_CPU_ARCH_PROTOCOL, &cpu_arch );
+
+/**
+ * Delay for a fixed number of microseconds
+ *
+ * @v usecs            Number of microseconds for which to delay
+ */
+static void efi_udelay ( unsigned long usecs ) {
+       EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+       EFI_STATUS efirc;
+       int rc;
+
+       if ( ( efirc = bs->Stall ( usecs ) ) != 0 ) {
+               rc = -EEFI ( efirc );
+               DBG ( "EFI could not delay for %ldus: %s\n",
+                     usecs, strerror ( rc ) );
+               /* Probably screwed */
+       }
+}
+
+/**
+ * Get current system time in ticks
+ *
+ * @ret ticks          Current time, in ticks
+ */
+static unsigned long efi_currticks ( void ) {
+       UINT64 time;
+       EFI_STATUS efirc;
+       int rc;
+
+       /* Read CPU timer 0 (TSC) */
+       if ( ( efirc = cpu_arch->GetTimerValue ( cpu_arch, 0, &time,
+                                                NULL ) ) != 0 ) {
+               rc = -EEFI ( efirc );
+               DBG ( "EFI could not read CPU timer: %s\n", strerror ( rc ) );
+               /* Probably screwed */
+               return -1UL;
+       }
+
+       return ( time >> EFI_TIMER0_SHIFT );
+}
+
+/**
+ * Get number of ticks per second
+ *
+ * @ret ticks_per_sec  Number of ticks per second
+ */
+static unsigned long efi_ticks_per_sec ( void ) {
+       static unsigned long ticks_per_sec = 0;
+
+       /* Calibrate timer, if necessary.  EFI does nominally provide
+        * the timer speed via the (optional) TimerPeriod parameter to
+        * the GetTimerValue() call, but it gets the speed slightly
+        * wrong.  By up to three orders of magnitude.  Not helpful.
+        */
+       if ( ! ticks_per_sec ) {
+               unsigned long start;
+               unsigned long elapsed;
+
+               DBG ( "Calibrating EFI timer with a %d ms delay\n",
+                     EFI_CALIBRATE_DELAY_MS );
+               start = currticks();
+               mdelay ( EFI_CALIBRATE_DELAY_MS );
+               elapsed = ( currticks() - start );
+               ticks_per_sec = ( elapsed * ( 1000 / EFI_CALIBRATE_DELAY_MS ));
+               DBG ( "EFI CPU timer calibrated at %ld ticks in %d ms (%ld "
+                     "ticks/sec)\n", elapsed, EFI_CALIBRATE_DELAY_MS,
+                     ticks_per_sec );
+       }
+
+       return ticks_per_sec;
+}
+
+PROVIDE_TIMER ( efi, udelay, efi_udelay );
+PROVIDE_TIMER ( efi, currticks, efi_currticks );
+PROVIDE_TIMER ( efi, ticks_per_sec, efi_ticks_per_sec );