[edk2-devel] [edk2-staging/RiscV64QemuVirt PATCH 14/29] UefiCpuPkg/CpuTimerLib: Add support for RISC-V
Sunil V L
sunilvl at ventanamicro.com
Mon Oct 10 10:11:47 UTC 2022
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4076
This is mostly copied from
edk2-platforms/Silicon/RISC-V/ProcessorPkg/Library/RiscVTimerLib
Cc: Eric Dong <eric.dong at intel.com>
Cc: Ray Ni <ray.ni at intel.com>
Cc: Rahul Kumar <rahul1.kumar at intel.com>
Cc: Daniel Schaefer <git at danielschaefer.me>
Signed-off-by: Sunil V L <sunilvl at ventanamicro.com>
---
.../Library/CpuTimerLib/BaseCpuTimerLib.inf | 3 +
.../Library/CpuTimerLib/RiscV64/CpuTimerLib.c | 199 ++++++++++++++++++
2 files changed, 202 insertions(+)
create mode 100644 UefiCpuPkg/Library/CpuTimerLib/RiscV64/CpuTimerLib.c
diff --git a/UefiCpuPkg/Library/CpuTimerLib/BaseCpuTimerLib.inf b/UefiCpuPkg/Library/CpuTimerLib/BaseCpuTimerLib.inf
index a22457b44940..554ce9fe9db8 100644
--- a/UefiCpuPkg/Library/CpuTimerLib/BaseCpuTimerLib.inf
+++ b/UefiCpuPkg/Library/CpuTimerLib/BaseCpuTimerLib.inf
@@ -22,6 +22,9 @@ [Sources.IA32, Sources.X64]
Ia32_X64/CpuTimerLib.c
Ia32_X64/BaseCpuTimerLib.c
+[Sources.RISCV64]
+ RiscV64/CpuTimerLib.c
+
[Packages]
MdePkg/MdePkg.dec
UefiCpuPkg/UefiCpuPkg.dec
diff --git a/UefiCpuPkg/Library/CpuTimerLib/RiscV64/CpuTimerLib.c b/UefiCpuPkg/Library/CpuTimerLib/RiscV64/CpuTimerLib.c
new file mode 100644
index 000000000000..9c8efc0f3530
--- /dev/null
+++ b/UefiCpuPkg/Library/CpuTimerLib/RiscV64/CpuTimerLib.c
@@ -0,0 +1,199 @@
+/** @file
+ RISC-V instance of Timer Library.
+
+ Copyright (c) 2016 - 2022, Hewlett Packard Enterprise Development LP. All rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Uefi.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/PcdLib.h>
+#include <Register/RiscV64/RiscVImpl.h>
+
+/**
+ Stalls the CPU for at least the given number of ticks.
+
+ Stalls the CPU for at least the given number of ticks. It's invoked by
+ MicroSecondDelay() and NanoSecondDelay().
+
+ @param Delay A period of time to delay in ticks.
+
+**/
+VOID
+InternalRiscVTimerDelay (
+ IN UINT32 Delay
+ )
+{
+ UINT32 Ticks;
+ UINT32 Times;
+
+ Times = Delay >> (RISCV_TIMER_COMPARE_BITS - 2);
+ Delay &= ((1 << (RISCV_TIMER_COMPARE_BITS - 2)) - 1);
+ do {
+ //
+ // The target timer count is calculated here
+ //
+ Ticks = RiscVReadTimer () + Delay;
+ Delay = 1 << (RISCV_TIMER_COMPARE_BITS - 2);
+ while (((Ticks - RiscVReadTimer ()) & (1 << (RISCV_TIMER_COMPARE_BITS - 1))) == 0) {
+ CpuPause ();
+ }
+ } while (Times-- > 0);
+}
+
+/**
+ Stalls the CPU for at least the given number of microseconds.
+
+ Stalls the CPU for the number of microseconds specified by MicroSeconds.
+
+ @param MicroSeconds The minimum number of microseconds to delay.
+
+ @return MicroSeconds
+
+**/
+UINTN
+EFIAPI
+MicroSecondDelay (
+ IN UINTN MicroSeconds
+ )
+{
+ InternalRiscVTimerDelay (
+ (UINT32)DivU64x32 (
+ MultU64x32 (
+ MicroSeconds,
+ PcdGet64 (PcdCpuCoreCrystalClockFrequency)
+ ),
+ 1000000u
+ )
+ );
+ return MicroSeconds;
+}
+
+/**
+ Stalls the CPU for at least the given number of nanoseconds.
+
+ Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
+
+ @param NanoSeconds The minimum number of nanoseconds to delay.
+
+ @return NanoSeconds
+
+**/
+UINTN
+EFIAPI
+NanoSecondDelay (
+ IN UINTN NanoSeconds
+ )
+{
+ InternalRiscVTimerDelay (
+ (UINT32)DivU64x32 (
+ MultU64x32 (
+ NanoSeconds,
+ PcdGet64 (PcdCpuCoreCrystalClockFrequency)
+ ),
+ 1000000000u
+ )
+ );
+ return NanoSeconds;
+}
+
+/**
+ Retrieves the current value of a 64-bit free running performance counter.
+
+ Retrieves the current value of a 64-bit free running performance counter. The
+ counter can either count up by 1 or count down by 1. If the physical
+ performance counter counts by a larger increment, then the counter values
+ must be translated. The properties of the counter can be retrieved from
+ GetPerformanceCounterProperties().
+
+ @return The current value of the free running performance counter.
+
+**/
+UINT64
+EFIAPI
+GetPerformanceCounter (
+ VOID
+ )
+{
+ return (UINT64)RiscVReadTimer ();
+}
+
+/**return
+ Retrieves the 64-bit frequency in Hz and the range of performance counter
+ values.
+
+ If StartValue is not NULL, then the value that the performance counter starts
+ with immediately after is it rolls over is returned in StartValue. If
+ EndValue is not NULL, then the value that the performance counter end with
+ immediately before it rolls over is returned in EndValue. The 64-bit
+ frequency of the performance counter in Hz is always returned. If StartValue
+ is less than EndValue, then the performance counter counts up. If StartValue
+ is greater than EndValue, then the performance counter counts down. For
+ example, a 64-bit free running counter that counts up would have a StartValue
+ of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
+ that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
+
+ @param StartValue The value the performance counter starts with when it
+ rolls over.
+ @param EndValue The value that the performance counter ends with before
+ it rolls over.
+
+ @return The frequency in Hz.
+
+**/
+UINT64
+EFIAPI
+GetPerformanceCounterProperties (
+ OUT UINT64 *StartValue, OPTIONAL
+ OUT UINT64 *EndValue OPTIONAL
+ )
+{
+ if (StartValue != NULL) {
+ *StartValue = 0;
+ }
+
+ if (EndValue != NULL) {
+ *EndValue = 32 - 1;
+ }
+
+ return PcdGet64 (PcdCpuCoreCrystalClockFrequency);
+}
+
+/**
+ Converts elapsed ticks of performance counter to time in nanoseconds.
+
+ This function converts the elapsed ticks of running performance counter to
+ time value in unit of nanoseconds.
+
+ @param Ticks The number of elapsed ticks of running performance counter.
+
+ @return The elapsed time in nanoseconds.
+
+**/
+UINT64
+EFIAPI
+GetTimeInNanoSecond (
+ IN UINT64 Ticks
+ )
+{
+ UINT64 NanoSeconds;
+ UINT32 Remainder;
+
+ //
+ // Ticks
+ // Time = --------- x 1,000,000,000
+ // Frequency
+ //
+ NanoSeconds = MultU64x32 (DivU64x32Remainder (Ticks, PcdGet64 (PcdCpuCoreCrystalClockFrequency), &Remainder), 1000000000u);
+
+ //
+ // Frequency < 0x100000000, so Remainder < 0x100000000, then (Remainder * 1,000,000,000)
+ // will not overflow 64-bit.
+ //
+ NanoSeconds += DivU64x32 (MultU64x32 ((UINT64)Remainder, 1000000000u), PcdGet64 (PcdCpuCoreCrystalClockFrequency));
+
+ return NanoSeconds;
+}
--
2.25.1
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