This patch adds support to XenBusDxe for executing on ARM and AArch64 machines (the former only when built with GCC). It includes arch-specific implementations of XenHypercall2() and a GCC specific version of the XenBusDxe atomics. It also includes the ARM version of the xen.h header that originates in the Xen project.
Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org --- .../Include/IndustryStandard/Xen/arch-arm/xen.h | 436 +++++++++++++++++++++ OvmfPkg/Include/IndustryStandard/Xen/xen.h | 2 +- .../Library/XenHypercallLib/Aarch64/Hypercall.S | 26 ++ OvmfPkg/Library/XenHypercallLib/Arm/Hypercall.S | 25 ++ .../Library/XenHypercallLib/XenHypercallLibArm.inf | 37 ++ OvmfPkg/XenBusDxe/AtomicsGcc.c | 44 +++ OvmfPkg/XenBusDxe/XenBusDxe.inf | 3 + 7 files changed, 572 insertions(+), 1 deletion(-) create mode 100644 OvmfPkg/Include/IndustryStandard/Xen/arch-arm/xen.h create mode 100644 OvmfPkg/Library/XenHypercallLib/Aarch64/Hypercall.S create mode 100644 OvmfPkg/Library/XenHypercallLib/Arm/Hypercall.S create mode 100644 OvmfPkg/Library/XenHypercallLib/XenHypercallLibArm.inf create mode 100644 OvmfPkg/XenBusDxe/AtomicsGcc.c
diff --git a/OvmfPkg/Include/IndustryStandard/Xen/arch-arm/xen.h b/OvmfPkg/Include/IndustryStandard/Xen/arch-arm/xen.h new file mode 100644 index 000000000000..655a221f6337 --- /dev/null +++ b/OvmfPkg/Include/IndustryStandard/Xen/arch-arm/xen.h @@ -0,0 +1,436 @@ +/****************************************************************************** + * arch-arm.h + * + * Guest OS interface to ARM Xen. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to + * deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + * + * Copyright 2011 (C) Citrix Systems + */ + +#ifndef __XEN_PUBLIC_ARCH_ARM_H__ +#define __XEN_PUBLIC_ARCH_ARM_H__ + +/* + * `incontents 50 arm_abi Hypercall Calling Convention + * + * A hypercall is issued using the ARM HVC instruction. + * + * A hypercall can take up to 5 arguments. These are passed in + * registers, the first argument in x0/r0 (for arm64/arm32 guests + * respectively irrespective of whether the underlying hypervisor is + * 32- or 64-bit), the second argument in x1/r1, the third in x2/r2, + * the forth in x3/r3 and the fifth in x4/r4. + * + * The hypercall number is passed in r12 (arm) or x16 (arm64). In both + * cases the relevant ARM procedure calling convention specifies this + * is an inter-procedure-call scratch register (e.g. for use in linker + * stubs). This use does not conflict with use during a hypercall. + * + * The HVC ISS must contain a Xen specific TAG: XEN_HYPERCALL_TAG. + * + * The return value is in x0/r0. + * + * The hypercall will clobber x16/r12 and the argument registers used + * by that hypercall (except r0 which is the return value) i.e. in + * addition to x16/r12 a 2 argument hypercall will clobber x1/r1 and a + * 4 argument hypercall will clobber x1/r1, x2/r2 and x3/r3. + * + * Parameter structs passed to hypercalls are laid out according to + * the Procedure Call Standard for the ARM Architecture (AAPCS, AKA + * EABI) and Procedure Call Standard for the ARM 64-bit Architecture + * (AAPCS64). Where there is a conflict the 64-bit standard should be + * used regardless of guest type. Structures which are passed as + * hypercall arguments are always little endian. + * + * All memory which is shared with other entities in the system + * (including the hypervisor and other guests) must reside in memory + * which is mapped as Normal Inner-cacheable. This applies to: + * - hypercall arguments passed via a pointer to guest memory. + * - memory shared via the grant table mechanism (including PV I/O + * rings etc). + * - memory shared with the hypervisor (struct shared_info, struct + * vcpu_info, the grant table, etc). + * + * Any Inner cache allocation strategy (Write-Back, Write-Through etc) + * is acceptable. There is no restriction on the Outer-cacheability. + */ + +/* + * `incontents 55 arm_hcall Supported Hypercalls + * + * Xen on ARM makes extensive use of hardware facilities and therefore + * only a subset of the potential hypercalls are required. + * + * Since ARM uses second stage paging any machine/physical addresses + * passed to hypercalls are Guest Physical Addresses (Intermediate + * Physical Addresses) unless otherwise noted. + * + * The following hypercalls (and sub operations) are supported on the + * ARM platform. Other hypercalls should be considered + * unavailable/unsupported. + * + * HYPERVISOR_memory_op + * All generic sub-operations. + * + * In addition the following arch specific sub-ops: + * * XENMEM_add_to_physmap + * * XENMEM_add_to_physmap_batch + * + * HYPERVISOR_domctl + * All generic sub-operations, with the exception of: + * * XEN_DOMCTL_iomem_permission (not yet implemented) + * * XEN_DOMCTL_irq_permission (not yet implemented) + * + * HYPERVISOR_sched_op + * All generic sub-operations, with the exception of: + * * SCHEDOP_block -- prefer wfi hardware instruction + * + * HYPERVISOR_console_io + * All generic sub-operations + * + * HYPERVISOR_xen_version + * All generic sub-operations + * + * HYPERVISOR_event_channel_op + * All generic sub-operations + * + * HYPERVISOR_physdev_op + * No sub-operations are currenty supported + * + * HYPERVISOR_sysctl + * All generic sub-operations, with the exception of: + * * XEN_SYSCTL_page_offline_op + * * XEN_SYSCTL_get_pmstat + * * XEN_SYSCTL_pm_op + * + * HYPERVISOR_hvm_op + * Exactly these sub-operations are supported: + * * HVMOP_set_param + * * HVMOP_get_param + * + * HYPERVISOR_grant_table_op + * All generic sub-operations + * + * HYPERVISOR_vcpu_op + * Exactly these sub-operations are supported: + * * VCPUOP_register_vcpu_info + * * VCPUOP_register_runstate_memory_area + * + * + * Other notes on the ARM ABI: + * + * - struct start_info is not exported to ARM guests. + * + * - struct shared_info is mapped by ARM guests using the + * HYPERVISOR_memory_op sub-op XENMEM_add_to_physmap, passing + * XENMAPSPACE_shared_info as space parameter. + * + * - All the per-cpu struct vcpu_info are mapped by ARM guests using the + * HYPERVISOR_vcpu_op sub-op VCPUOP_register_vcpu_info, including cpu0 + * struct vcpu_info. + * + * - The grant table is mapped using the HYPERVISOR_memory_op sub-op + * XENMEM_add_to_physmap, passing XENMAPSPACE_grant_table as space + * parameter. The memory range specified under the Xen compatible + * hypervisor node on device tree can be used as target gpfn for the + * mapping. + * + * - Xenstore is initialized by using the two hvm_params + * HVM_PARAM_STORE_PFN and HVM_PARAM_STORE_EVTCHN. They can be read + * with the HYPERVISOR_hvm_op sub-op HVMOP_get_param. + * + * - The paravirtualized console is initialized by using the two + * hvm_params HVM_PARAM_CONSOLE_PFN and HVM_PARAM_CONSOLE_EVTCHN. They + * can be read with the HYPERVISOR_hvm_op sub-op HVMOP_get_param. + * + * - Event channel notifications are delivered using the percpu GIC + * interrupt specified under the Xen compatible hypervisor node on + * device tree. + * + * - The device tree Xen compatible node is fully described under Linux + * at Documentation/devicetree/bindings/arm/xen.txt. + */ + +#define XEN_HYPERCALL_TAG 0XEA1 + +#define uint64_aligned_t UINT64 __attribute__((aligned(8))) + +#ifndef __ASSEMBLY__ +#define ___DEFINE_XEN_GUEST_HANDLE(name, type) \ + typedef union { type *p; unsigned long q; } \ + __guest_handle_ ## name; \ + typedef union { type *p; uint64_aligned_t q; } \ + __guest_handle_64_ ## name; + +/* + * XEN_GUEST_HANDLE represents a guest pointer, when passed as a field + * in a struct in memory. On ARM is always 8 bytes sizes and 8 bytes + * aligned. + * XEN_GUEST_HANDLE_PARAM represent a guest pointer, when passed as an + * hypercall argument. It is 4 bytes on aarch and 8 bytes on aarch64. + */ +#define __DEFINE_XEN_GUEST_HANDLE(name, type) \ + ___DEFINE_XEN_GUEST_HANDLE(name, type); \ + ___DEFINE_XEN_GUEST_HANDLE(const_##name, const type) +#define DEFINE_XEN_GUEST_HANDLE(name) __DEFINE_XEN_GUEST_HANDLE(name, name) +#define __XEN_GUEST_HANDLE(name) __guest_handle_64_ ## name +#define XEN_GUEST_HANDLE(name) __XEN_GUEST_HANDLE(name) +/* this is going to be changed on 64 bit */ +#define XEN_GUEST_HANDLE_PARAM(name) __guest_handle_ ## name +#define set_xen_guest_handle_raw(hnd, val) \ + do { \ + typeof(&(hnd)) _sxghr_tmp = &(hnd); \ + _sxghr_tmp->q = 0; \ + _sxghr_tmp->p = val; \ + } while ( 0 ) +#ifdef __XEN_TOOLS__ +#define get_xen_guest_handle(val, hnd) do { val = (hnd).p; } while (0) +#endif +#define set_xen_guest_handle(hnd, val) set_xen_guest_handle_raw(hnd, val) + +#if defined(__GNUC__) && !defined(__STRICT_ANSI__) +/* Anonymous union includes both 32- and 64-bit names (e.g., r0/x0). */ +# define __DECL_REG(n64, n32) union { \ + UINT64 n64; \ + UINT32 n32; \ + } +#else +/* Non-gcc sources must always use the proper 64-bit name (e.g., x0). */ +#define __DECL_REG(n64, n32) UINT64 n64 +#endif + +struct vcpu_guest_core_regs +{ + /* Aarch64 Aarch32 */ + __DECL_REG(x0, r0_usr); + __DECL_REG(x1, r1_usr); + __DECL_REG(x2, r2_usr); + __DECL_REG(x3, r3_usr); + __DECL_REG(x4, r4_usr); + __DECL_REG(x5, r5_usr); + __DECL_REG(x6, r6_usr); + __DECL_REG(x7, r7_usr); + __DECL_REG(x8, r8_usr); + __DECL_REG(x9, r9_usr); + __DECL_REG(x10, r10_usr); + __DECL_REG(x11, r11_usr); + __DECL_REG(x12, r12_usr); + + __DECL_REG(x13, sp_usr); + __DECL_REG(x14, lr_usr); + + __DECL_REG(x15, __unused_sp_hyp); + + __DECL_REG(x16, lr_irq); + __DECL_REG(x17, sp_irq); + + __DECL_REG(x18, lr_svc); + __DECL_REG(x19, sp_svc); + + __DECL_REG(x20, lr_abt); + __DECL_REG(x21, sp_abt); + + __DECL_REG(x22, lr_und); + __DECL_REG(x23, sp_und); + + __DECL_REG(x24, r8_fiq); + __DECL_REG(x25, r9_fiq); + __DECL_REG(x26, r10_fiq); + __DECL_REG(x27, r11_fiq); + __DECL_REG(x28, r12_fiq); + + __DECL_REG(x29, sp_fiq); + __DECL_REG(x30, lr_fiq); + + /* Return address and mode */ + __DECL_REG(pc64, pc32); /* ELR_EL2 */ + UINT32 cpsr; /* SPSR_EL2 */ + + union { + UINT32 spsr_el1; /* AArch64 */ + UINT32 spsr_svc; /* AArch32 */ + }; + + /* AArch32 guests only */ + UINT32 spsr_fiq, spsr_irq, spsr_und, spsr_abt; + + /* AArch64 guests only */ + UINT64 sp_el0; + UINT64 sp_el1, elr_el1; +}; +typedef struct vcpu_guest_core_regs vcpu_guest_core_regs_t; +DEFINE_XEN_GUEST_HANDLE(vcpu_guest_core_regs_t); + +#undef __DECL_REG + +typedef UINT64 xen_pfn_t; +#define PRI_xen_pfn PRIx64 + +/* Maximum number of virtual CPUs in legacy multi-processor guests. */ +/* Only one. All other VCPUS must use VCPUOP_register_vcpu_info */ +#define XEN_LEGACY_MAX_VCPUS 1 + +typedef UINT64 xen_ulong_t; +#define PRI_xen_ulong PRIx64 + +#if defined(__XEN__) || defined(__XEN_TOOLS__) +struct vcpu_guest_context { +#define _VGCF_online 0 +#define VGCF_online (1<<_VGCF_online) + UINT32 flags; /* VGCF_* */ + + struct vcpu_guest_core_regs user_regs; /* Core CPU registers */ + + UINT32 sctlr; + UINT64 ttbcr, ttbr0, ttbr1; +}; +typedef struct vcpu_guest_context vcpu_guest_context_t; +DEFINE_XEN_GUEST_HANDLE(vcpu_guest_context_t); +#endif + +struct arch_vcpu_info { +}; +typedef struct arch_vcpu_info arch_vcpu_info_t; + +struct arch_shared_info { +}; +typedef struct arch_shared_info arch_shared_info_t; +typedef UINT64 xen_callback_t; + +#endif + +#if defined(__XEN__) || defined(__XEN_TOOLS__) + +/* PSR bits (CPSR, SPSR)*/ + +#define PSR_THUMB (1<<5) /* Thumb Mode enable */ +#define PSR_FIQ_MASK (1<<6) /* Fast Interrupt mask */ +#define PSR_IRQ_MASK (1<<7) /* Interrupt mask */ +#define PSR_ABT_MASK (1<<8) /* Asynchronous Abort mask */ +#define PSR_BIG_ENDIAN (1<<9) /* arm32: Big Endian Mode */ +#define PSR_DBG_MASK (1<<9) /* arm64: Debug Exception mask */ +#define PSR_IT_MASK (0x0600fc00) /* Thumb If-Then Mask */ +#define PSR_JAZELLE (1<<24) /* Jazelle Mode */ + +/* 32 bit modes */ +#define PSR_MODE_USR 0x10 +#define PSR_MODE_FIQ 0x11 +#define PSR_MODE_IRQ 0x12 +#define PSR_MODE_SVC 0x13 +#define PSR_MODE_MON 0x16 +#define PSR_MODE_ABT 0x17 +#define PSR_MODE_HYP 0x1a +#define PSR_MODE_UND 0x1b +#define PSR_MODE_SYS 0x1f + +/* 64 bit modes */ +#define PSR_MODE_BIT 0x10 /* Set iff AArch32 */ +#define PSR_MODE_EL3h 0x0d +#define PSR_MODE_EL3t 0x0c +#define PSR_MODE_EL2h 0x09 +#define PSR_MODE_EL2t 0x08 +#define PSR_MODE_EL1h 0x05 +#define PSR_MODE_EL1t 0x04 +#define PSR_MODE_EL0t 0x00 + +#define PSR_GUEST32_INIT (PSR_ABT_MASK|PSR_FIQ_MASK|PSR_IRQ_MASK|PSR_MODE_SVC) +#define PSR_GUEST64_INIT (PSR_ABT_MASK|PSR_FIQ_MASK|PSR_IRQ_MASK|PSR_MODE_EL1h) + +#define SCTLR_GUEST_INIT 0x00c50078 + +/* + * Virtual machine platform (memory layout, interrupts) + * + * These are defined for consistency between the tools and the + * hypervisor. Guests must not rely on these hardcoded values but + * should instead use the FDT. + */ + +/* Physical Address Space */ + +/* vGIC mappings: Only one set of mapping is used by the guest. + * Therefore they can overlap. + */ + +/* vGIC v2 mappings */ +#define GUEST_GICD_BASE 0x03001000ULL +#define GUEST_GICD_SIZE 0x00001000ULL +#define GUEST_GICC_BASE 0x03002000ULL +#define GUEST_GICC_SIZE 0x00000100ULL + +/* vGIC v3 mappings */ +#define GUEST_GICV3_GICD_BASE 0x03001000ULL +#define GUEST_GICV3_GICD_SIZE 0x00010000ULL + +#define GUEST_GICV3_RDIST_STRIDE 0x20000ULL +#define GUEST_GICV3_RDIST_REGIONS 1 + +#define GUEST_GICV3_GICR0_BASE 0x03020000ULL /* vCPU0 - vCPU7 */ +#define GUEST_GICV3_GICR0_SIZE 0x00100000ULL + +/* 16MB == 4096 pages reserved for guest to use as a region to map its + * grant table in. + */ +#define GUEST_GNTTAB_BASE 0x38000000ULL +#define GUEST_GNTTAB_SIZE 0x01000000ULL + +#define GUEST_MAGIC_BASE 0x39000000ULL +#define GUEST_MAGIC_SIZE 0x01000000ULL + +#define GUEST_RAM_BANKS 2 + +#define GUEST_RAM0_BASE 0x40000000ULL /* 3GB of low RAM @ 1GB */ +#define GUEST_RAM0_SIZE 0xc0000000ULL + +#define GUEST_RAM1_BASE 0x0200000000ULL /* 1016GB of RAM @ 8GB */ +#define GUEST_RAM1_SIZE 0xfe00000000ULL + +#define GUEST_RAM_BASE GUEST_RAM0_BASE /* Lowest RAM address */ +/* Largest amount of actual RAM, not including holes */ +#define GUEST_RAM_MAX (GUEST_RAM0_SIZE + GUEST_RAM1_SIZE) +/* Suitable for e.g. const uint64_t ramfoo[] = GUEST_RAM_BANK_FOOS; */ +#define GUEST_RAM_BANK_BASES { GUEST_RAM0_BASE, GUEST_RAM1_BASE } +#define GUEST_RAM_BANK_SIZES { GUEST_RAM0_SIZE, GUEST_RAM1_SIZE } + +/* Interrupts */ +#define GUEST_TIMER_VIRT_PPI 27 +#define GUEST_TIMER_PHYS_S_PPI 29 +#define GUEST_TIMER_PHYS_NS_PPI 30 +#define GUEST_EVTCHN_PPI 31 + +/* PSCI functions */ +#define PSCI_cpu_suspend 0 +#define PSCI_cpu_off 1 +#define PSCI_cpu_on 2 +#define PSCI_migrate 3 + +#endif + +#endif /* __XEN_PUBLIC_ARCH_ARM_H__ */ + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * tab-width: 4 + * indent-tabs-mode: nil + * End: + */ diff --git a/OvmfPkg/Include/IndustryStandard/Xen/xen.h b/OvmfPkg/Include/IndustryStandard/Xen/xen.h index 79697fcb6152..f38a22be4e16 100644 --- a/OvmfPkg/Include/IndustryStandard/Xen/xen.h +++ b/OvmfPkg/Include/IndustryStandard/Xen/xen.h @@ -32,7 +32,7 @@ #if defined(MDE_CPU_IA32) || defined(MDE_CPU_X64) #include "arch-x86/xen.h" #elif defined(__arm__) || defined (__aarch64__) -#include "arch-arm.h" +#include "arch-arm/xen.h" #else #error "Unsupported architecture" #endif diff --git a/OvmfPkg/Library/XenHypercallLib/Aarch64/Hypercall.S b/OvmfPkg/Library/XenHypercallLib/Aarch64/Hypercall.S new file mode 100644 index 000000000000..b1b5d4cc3f28 --- /dev/null +++ b/OvmfPkg/Library/XenHypercallLib/Aarch64/Hypercall.S @@ -0,0 +1,26 @@ + +/** @file + AArch64 implementation of XenHypercall2 + + Copyright (C) 2014, Linaro Ltd. + + This program and the accompanying materials + are licensed and made available under the terms and conditions of the BSD License + which accompanies this distribution. The full text of the license may be found at + http://opensource.org/licenses/bsd-license.php + + THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, + WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + +**/ + +#include <IndustryStandard/Xen/arch-arm/xen.h> + + .text + .global ASM_PFX(XenHypercall2) +ASM_PFX(XenHypercall2): + mov x16, x0 + mov x0, x1 + mov x1, x2 + hvc #XEN_HYPERCALL_TAG + ret diff --git a/OvmfPkg/Library/XenHypercallLib/Arm/Hypercall.S b/OvmfPkg/Library/XenHypercallLib/Arm/Hypercall.S new file mode 100644 index 000000000000..b38e1a8f18da --- /dev/null +++ b/OvmfPkg/Library/XenHypercallLib/Arm/Hypercall.S @@ -0,0 +1,25 @@ +/** @file + ARM (AArch32) implementation of XenHypercall2 + + Copyright (C) 2014, Linaro Ltd. + + This program and the accompanying materials + are licensed and made available under the terms and conditions of the BSD License + which accompanies this distribution. The full text of the license may be found at + http://opensource.org/licenses/bsd-license.php + + THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, + WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + +**/ + +#include <IndustryStandard/Xen/arch-arm/xen.h> + + .text + .global ASM_PFX(XenHypercall2) +ASM_PFX(XenHypercall2): + mov r12, r0 + mov r0, r1 + mov r1, r2 + hvc #XEN_HYPERCALL_TAG + bx lr diff --git a/OvmfPkg/Library/XenHypercallLib/XenHypercallLibArm.inf b/OvmfPkg/Library/XenHypercallLib/XenHypercallLibArm.inf new file mode 100644 index 000000000000..7ba513f39355 --- /dev/null +++ b/OvmfPkg/Library/XenHypercallLib/XenHypercallLibArm.inf @@ -0,0 +1,37 @@ +## @file +# Xen Hypercall abstraction lib for ARM architecture +# +# Copyright (c) 2014, Linaro Ltd. All rights reserved.<BR> +# This program and the accompanying materials +# are licensed and made available under the terms and conditions of the BSD License +# which accompanies this distribution. The full text of the license may be found at +# http://opensource.org/licenses/bsd-license.php +# +# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. +# +## + +[Defines] + INF_VERSION = 0x00010005 + BASE_NAME = XenHypercallLibArm + FILE_GUID = 9607AC2E-FCB9-499B-9475-612282019568 + MODULE_TYPE = BASE + VERSION_STRING = 1.0 + LIBRARY_CLASS = XenHypercallLib|DXE_DRIVER UEFI_DRIVER + +# +# The following information is for reference only and not required by the build tools. +# +# VALID_ARCHITECTURES = ARM AARCH64 +# + +[Sources.ARM] + Arm/Hypercall.S + +[Sources.AARCH64] + Aarch64/Hypercall.S + +[Packages] + MdePkg/MdePkg.dec + OvmfPkg/OvmfPkg.dec diff --git a/OvmfPkg/XenBusDxe/AtomicsGcc.c b/OvmfPkg/XenBusDxe/AtomicsGcc.c new file mode 100644 index 000000000000..a0bdcbf67440 --- /dev/null +++ b/OvmfPkg/XenBusDxe/AtomicsGcc.c @@ -0,0 +1,44 @@ +/** @file + Arch-independent implementations of XenBusDxe atomics using GCC __builtins + + Copyright (C) 2014, Linaro Ltd. + + This program and the accompanying materials + are licensed and made available under the terms and conditions of the BSD License + which accompanies this distribution. The full text of the license may be found at + http://opensource.org/licenses/bsd-license.php + + THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, + WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + +**/ + +UINT16 +EFIAPI +InternalSyncCompareExchange16 ( + IN volatile UINT16 *Value, + IN UINT16 CompareValue, + IN UINT16 ExchangeValue + ) +{ + return __sync_val_compare_and_swap_2 (Value, CompareValue, ExchangeValue); +} + +INT32 +EFIAPI +TestAndClearBit ( + IN INT32 Bit, + IN volatile VOID *Address + ) +{ + // + // Calculate the effective address relative to 'Address' based on the + // higher order bits of 'Bit'. Use signed shift instead of division to + // ensure we round towards -Inf, and end up with a positive shift in 'Bit', + // even if 'Bit' itself is negative. + // + Address += (Bit >> 5) * sizeof(INT32); + Bit &= 31; + + return (__sync_fetch_and_and_4 (Address, ~(1U << Bit)) & (1U << Bit)) != 0; +} diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.inf b/OvmfPkg/XenBusDxe/XenBusDxe.inf index 1429a85e1d12..19c9a5dd7927 100644 --- a/OvmfPkg/XenBusDxe/XenBusDxe.inf +++ b/OvmfPkg/XenBusDxe/XenBusDxe.inf @@ -56,6 +56,9 @@ X64/InterlockedCompareExchange16.nasm X64/TestAndClearBit.nasm
+[Sources.AARCH64, Sources.ARM] + AtomicsGcc.c | GCC + [LibraryClasses] UefiDriverEntryPoint UefiBootServicesTableLib