X-Git-Url: https://git.proxmox.com/?p=qemu.git;a=blobdiff_plain;f=qemu-tech.texi;h=8aefa743a8b7c1dbed925412799a3a9a4b99e174;hp=52560dcf964340fd90143afb68e4f91a92746ca7;hb=60aad298cb6de52f2716b2e82e1353ea9de95fd6;hpb=a1a32b05bbaabe7c7179564e25750393f2271eef diff --git a/qemu-tech.texi b/qemu-tech.texi index 52560dcf9..8aefa743a 100644 --- a/qemu-tech.texi +++ b/qemu-tech.texi @@ -1,6 +1,10 @@ \input texinfo @c -*- texinfo -*- @c %**start of header @setfilename qemu-tech.info + +@documentlanguage en +@documentencoding UTF-8 + @settitle QEMU Internals @exampleindent 0 @paragraphindent 0 @@ -38,13 +42,14 @@ @chapter Introduction @menu -* intro_features:: Features -* intro_x86_emulation:: x86 and x86-64 emulation -* intro_arm_emulation:: ARM emulation -* intro_mips_emulation:: MIPS emulation -* intro_ppc_emulation:: PowerPC emulation -* intro_sparc_emulation:: Sparc32 and Sparc64 emulation -* intro_other_emulation:: Other CPU emulation +* intro_features:: Features +* intro_x86_emulation:: x86 and x86-64 emulation +* intro_arm_emulation:: ARM emulation +* intro_mips_emulation:: MIPS emulation +* intro_ppc_emulation:: PowerPC emulation +* intro_sparc_emulation:: Sparc32 and Sparc64 emulation +* intro_xtensa_emulation:: Xtensa emulation +* intro_other_emulation:: Other CPU emulation @end menu @node intro_features @@ -91,10 +96,6 @@ Alpha and S390 hosts, but TCG (see below) doesn't support those yet. @item Precise exceptions support. -@item The virtual CPU is a library (@code{libqemu}) which can be used -in other projects (look at @file{qemu/tests/qruncom.c} to have an -example of user mode @code{libqemu} usage). - @item Floating point library supporting both full software emulation and native host FPU instructions. @@ -111,8 +112,7 @@ QEMU user mode emulation features: @end itemize Linux user emulator (Linux host only) can be used to launch the Wine -Windows API emulator (@url{http://www.winehq.org}). A Darwin user -emulator (Darwin hosts only) exists and a BSD user emulator for BSD +Windows API emulator (@url{http://www.winehq.org}). A BSD user emulator for BSD hosts is under development. It would also be possible to develop a similar user emulator for Solaris. @@ -255,6 +255,31 @@ Current QEMU limitations: @end itemize +@node intro_xtensa_emulation +@section Xtensa emulation + +@itemize + +@item Core Xtensa ISA emulation, including most options: code density, +loop, extended L32R, 16- and 32-bit multiplication, 32-bit division, +MAC16, miscellaneous operations, boolean, FP coprocessor, coprocessor +context, debug, multiprocessor synchronization, +conditional store, exceptions, relocatable vectors, unaligned exception, +interrupts (including high priority and timer), hardware alignment, +region protection, region translation, MMU, windowed registers, thread +pointer, processor ID. + +@item Not implemented options: data/instruction cache (including cache +prefetch and locking), XLMI, processor interface. Also options not +covered by the core ISA (e.g. FLIX, wide branches) are not implemented. + +@item Can run most Xtensa Linux binaries. + +@item New core configuration that requires no additional instructions +may be created from overlay with minimal amount of hand-written code. + +@end itemize + @node intro_other_emulation @section Other CPU emulation @@ -405,7 +430,7 @@ generate an addition for the segment base. @node Translation cache @section Translation cache -A 16 MByte cache holds the most recently used translations. For +A 32 MByte cache holds the most recently used translations. For simplicity, it is completely flushed when it is full. A translation unit contains just a single basic block (a block of x86 instructions terminated by a jump or by a virtual CPU state change which the @@ -511,8 +536,8 @@ timers, especially together with the use of bottom halves (BHs). @node Hardware interrupts @section Hardware interrupts -In order to be faster, QEMU does not check at every basic block if an -hardware interrupt is pending. Instead, the user must asynchrously +In order to be faster, QEMU does not check at every basic block if a +hardware interrupt is pending. Instead, the user must asynchronously call a specific function to tell that an interrupt is pending. This function resets the chaining of the currently executing basic block. It ensures that the execution will return soon in the main loop @@ -544,7 +569,7 @@ Linux kernel does. The @code{sigreturn()} system call is emulated to return from the virtual signal handler. Some signals (such as SIGALRM) directly come from the host. Other -signals are synthetized from the virtual CPU exceptions such as SIGFPE +signals are synthesized from the virtual CPU exceptions such as SIGFPE when a division by zero is done (see @code{main.c:cpu_loop()}). The blocked signal mask is still handled by the host Linux kernel so @@ -655,7 +680,6 @@ are available. They are used for regression testing. @menu * test-i386:: * linux-test:: -* qruncom.c:: @end menu @node test-i386 @@ -681,11 +705,6 @@ This program tests various Linux system calls. It is used to verify that the system call parameters are correctly converted between target and host CPUs. -@node qruncom.c -@section @file{qruncom.c} - -Example of usage of @code{libqemu} to emulate a user mode i386 CPU. - @node Index @chapter Index @printindex cp