标题: ARM 32 物理地址与虚拟地址转换（2） [打印本页] 作者: ulppknot 时间: 2019-7-1 14:38 标题: ARM 32 物理地址与虚拟地址转换（2） 第二章 虚拟地址到物理地址转换 6 A& t8 l: D9 x. } 7 r9 n4 h" E* G8 ~5 j& Q' P2 e( b2.1 MMU 硬件VA到PA转换 9 @1 X: d! ^# ]* C$ D+ Y4 g. T2 a# U4 [% R; a7 T. [
9850K 的cpu是Cortex A7的。 , D( Z9 m; W: u9 F# k* @' O, e0 @$ H; T+ a
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The Cortex-A7 MPCore processorimplements the Extended VMSAv7 MMU, which includes the ARMv7-A Virtual MemorySystem Architecture (VMSA), the Security Extensions, the Large Physical AddressExtensions (LPAE), and the Virtualization Extensions.5 l1 W X# i) |" b
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VMSAv7 defines two alternativetranslation table formats: ' ^+ b+ [: F, h 9 b; c; |7 ^* w9 D$ S; T! K & e% ^3 {! E: O3 e% nShort-descriptor format % J' E) u5 y! X$ h0 k0 E' n& w , y! {+ n; P, D7 a. ] % a+ q3 Q4 H: g4 f: k! {' AThis is the original format definedin issue A of this Architecture Reference Manual, and is the only 1 d% Q; [# {5 D2 b: M$ [+ X! O: S! r9 L1 q% x
, \ e9 g8 m- W6 z. n5 l) Rformat supported on implementationsthat do not include the Large Physical Address Extension. It3 L, |% | {# ^, ~& M
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uses 32-bit descriptor entries inthe translation tables, and provides:+ H, y# n) S1 U
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• Up to two levels of address lookup.6 @! |3 v1 u& X$ u( e
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8 I7 I( X7 P C* w! h6 y& H• 32-bit input addresses.4 m7 I: y) R. g" E( o' e8 H! r
/ T& Q: D! m1 D7 C. }. N2 Y4 Y 0 C$ w6 ]8 g, R- h• Output addresses of up to 40 bits.% D& s L+ f6 ^3 f6 |" t
* ^. E, Q0 W* O' {" z: @5 F : r, J R2 `& Y9 y4 j. G7 _" o• Support for PAs of more than 32 bits by use of supersections, with16MB granularity. / M* h3 H4 M1 N* `1 F+ @! P, I0 t; _* \2 y" X s
0 M- @8 n* L- j' K9 S; N) d6 w• Support for No access, Client, and Manager domains.: P, k6 q0 R3 ~' F$ H, n
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• 32-bit table entries. / u; A4 u- Q. ?- S8 V9 ? 2 I1 i" F- s; j# `1 O4 n. ^# {# _* h( U, J. u0 V
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