网站开发合作运营平台合同,我的网站百度找不到,12306的网站建设,公司网站申请目录 1、gic的版本2、GICv3/gicv4的模型图3、gic中断号的划分4、GIC连接方式5、gic的状态6、gic框架7、gic Configuring推荐 本文转自 周贺贺#xff0c;baron#xff0c;代码改变世界ctw#xff0c;Arm精选#xff0c; armv8/armv9#xff0c;trustzone/tee#xff0c;s… 目录 1、gic的版本2、GICv3/gicv4的模型图3、gic中断号的划分4、GIC连接方式5、gic的状态6、gic框架7、gic Configuring推荐 本文转自 周贺贺baron代码改变世界ctwArm精选 armv8/armv9trustzone/teesecureboot资深安全架构专家11年手机安全/SOC底层安全开发经验。擅长trustzone/tee安全产品的设计和开发。 1、gic的版本
GIC是一个为Cortex-A和Arm Cortex-R设计的标准的中断控制器
2、GICv3/gicv4的模型图 3、gic中断号的划分 Shared Peripheral Interrupt (SPI) Private Peripheral Interrupt (PPI) Software Generated Interrupt (SGI) Locality-specific Peripheral Interrupt (LPI) 使用示例
4、GIC连接方式 5、gic的状态 中断的生命周期: 对于电平触发的中断(level-sensitive interrupts)一个上升沿输入将中断变成pending中断信号线保持高电平直到PE断言该中断信号. 对于边沿触发的中断(edge-sensitive interrupts)一个上升沿输入将中断变成pending中断信号线不会保持高电平.
6、gic框架
• Distributor interface • Redistributor interface • CPU interface
Distributor (GICD_*) for SPIs • Interrupt prioritization and distribution of SPIs • Enable and disable SPIs • Set the priority level of each SPI • Route information for each SPI • Set each SPI to be level-sensitive or edge-triggered • Generate message-signaled SPIs • Control the active and pending state of SPIs • Determine the programmer’s model that is used in each Security state: affinity routing or legacy
Redistributors (GICR_*) • Enable and disable SGIs and PPIs • Set the priority level of SGIs and PPIs • Set each PPI to be level-sensitive or edge-triggered • Assign each SGI and PPI to an interrupt group • Control the state of SGIs and PPIs • Control the base address for the data structures in memory that support the associated interrupt properties and pending state for LPIs • Provide power management support for the connected PE
CPU interfaces (ICC_*_ELn) • Provide general control and configuration to enable interrupt handling • Acknowledge an interrupt • Perform a priority drop and deactivation of interrupts • Set an interrupt priority mask for the PE • Define the preemption policy for the PE • Determine the highest priority pending interrupt for the PE
In Arm CoreLink GICv3, the CPU Interface registers are accessed as System registers: ICC_*_ELn.
7、gic Configuring
全局配置 GICD_CTLR.ARE: Enable Affinity routing (ARE bits), 1-使用gicv3 mode0-使用legacy mode(gicv2 mode). 默认为1 GICD_CTLR.EnableGrp1S GICD_CTLR.EnableGrp1NS GICD_CTLR.EnableGrp0
注意在GIC-600 does not support legacy operation
(Redistributor)Settings for each PE Redistributor中包含了一个GICR_WAKER寄存器用于记录connected PE的状态是onLine还是offline. 如果让PE变成online软件则必需这样做 • Clear GICR_WAKER.ProcessorSleep to 0. • Poll GICR_WAKER.ChildrenAsleep until it reads 0
如果PE is offline (GICR_WAKER.ProcessorSleep1)时来了一个中断target到该PE上将产一个wake request信号这个信号连接PE的power controller该controller将会打开PE。然后PE clear the ProcessorSleep bit
CPU interfaces (ICC_*_ELn)
SRE bit— enable cpu interface 注有些处理器可能不支持legacy operationSRE比特位也是固定为1那么软件就不需要处理该比特了
Set Priority Mask and Binary Point registers ICC_PMR_EL1、ICC_BPRn_EL1
Set EOI mode EOI:End of interrupt ICC_CTLR_EL1 and ICC_CTLR_EL3
Enable signaling of each interrupt group ICC_IGRPEN1_EL1 (banked by Security state) ICC_IGRPEN0_EL1
PE configuration
Routing controls - SCR_EL3 、 HCR_EL2Interrupt masks - PSTATEVector table - VBAR_ELn
interrupt sources configuration
SPIs are configured through the Distributor, using the GICD_* registers.PPIs and SGIs are configured through the individual Redistributors, using the GICR_* registers
对于每一个中断软件必需配置的
Priority: GICD_IPRIORITYn, GICR_IPRIORITYnGroup: GICD_IGROUPn, GICD_IGRPMODn, GICR_IGROUPn, GICR_IGRPMODnEdge-triggered or level-sensitive: GICD_ICFGRn, GICR_ICFGRnEnable: GICD_ISENABLERn, GICD_ICENABLER, GICR_ISENABLERn, GICR_ICENABLERn Setting the target PE for SPIs
GICD_IROUTERn.Interrupt_Routing_Mode 0 rounting到制定的PEGICD_IROUTERn.Interrupt_Routing_Mode 1 Distributor硬件会自动选择一个PE可以是0-n A PE can opt out of receiving 1-of-N interrupts. This is controlled by the DPG1S, DPG1NS and DPG0 bits in GICR_CTLR. Routing a pending interrupt to a PE
Check that the group associated with the interrupt is enabledCheck that the interrupt is enabledCheck the routing controls to decide which PEs can receive the interrupt. routing is controlled by GICD_IROUTERnAn SPI can target one specific PE, or any one of the connected PEsCheck the interrupt priority and priority mask to decide which PEs are suitable to handle the interrupt Each PE has a Priority Mask register, ICC_PMR_EL1, in its CPU interfaceCheck the running priority to decide which PEs are available to handle the interrup Only an interrupt with a higher priority than the running priority can preempt the current interrupt
软件读取中断号 中断优先级
中断结束End of interrupt
Priority drop - 将中断优先级降到中断产生之前的值Deactivation - 将中断从active变成inactive
在gicv3中drop和deactivation通常是一起打开的。
ICC_CTLR_ELn.EOImode 1: 通过写ICC_EOIR0_EL1、ICC_EOIR1_EL1让drop and deactivation同时生效 ICC_CTLR_ELn.EOImode 0: 通过写ICC_EOIR0_EL1、ICC_EOIR1_EL1让drop生效写ICC_DIR_EL1让deactivation生效这在虚拟化中会用到.
大多数的软件系统中 EOIMode0而下hypervisor的系统中 EOIMode1
中断号的状态 产生SGI中断 PE在secure执行时可以产生secure和non-secure的SGI; PE在non-secure执行时也是可以产生secure的SGI但是取决于GICR_NSACR寄存器的配置该寄存器只能在secure中读写
比较GICv3和GICv2 在gicv2中SGI INTIDs对于originating PE和the target PE是banked 在gicv3中SGI仅仅对target PE是banked
在gicv2中同时收到两个SGI5中断两个中断都会被PE处理。 而在gicv3上由于originating不是banked所有前一个SGI5中断将会丢失。PE只能收到一个
Legacy operation
When ARE0, affinity routing is disabled (legacy operation)When ARE1, affinity routing is enabled (GICv3 operation) 推荐
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