Re: [PATCH v36 00/17] QEMU AVR 8 bit cores

2019-11-26 Thread Aleksandar Markovic
On Sunday, November 24, 2019, Michael Rolnik  wrote:

> This series of patches adds 8bit AVR cores to QEMU.
> All instruction, except BREAK/DES/SPM/SPMX, are implemented. Not fully
> tested yet.
> However I was able to execute simple code with functions. e.g fibonacci
> calculation.
> This series of patches include a non real, sample board.
> No fuses support yet. PC is set to 0 at reset.
>
>
You used to complain why nobody is reviewing your code, now you will start
complaining that there are too many reviewes. ;-) Good sign if that
happens!!

the patches include the following
> 1. just a basic 8bit AVR CPU, without instruction decoding or translation
> 2. CPU features which allow define the following 8bit AVR cores
>  avr1
>  avr2 avr25
>  avr3 avr31 avr35
>  avr4
>  avr5 avr51
>  avr6
>  xmega2 xmega4 xmega5 xmega6 xmega7
> 3. a definition of sample machine with SRAM, FLASH and CPU which allows to
> execute simple code
> 4. encoding for all AVR instructions
> 5. interrupt handling
> 6. helpers for IN, OUT, SLEEP, WBR & unsupported instructions
> 7. a decoder which given an opcode decides what istruction it is
> 8. translation of AVR instruction into TCG
> 9. all features together
>
> changes since v3
> 1. rampD/X/Y/Z registers are encoded as 0x00ff (instead of 0x00ff)
> for faster address manipulaton
> 2. ffs changed to ctz32
> 3. duplicate code removed at avr_cpu_do_interrupt
> 4. using andc instead of not + and
> 5. fixing V flag calculation in varios instructions
> 6. freeing local variables in PUSH
> 7. tcg_const_local_i32 -> tcg_const_i32
> 8. using sextract32 instead of my implementation
> 9. fixing BLD instruction
> 10.xor(r) instead of 0xff - r at COM
> 11.fixing MULS/MULSU not to modify inputs' content
> 12.using SUB for NEG
> 13.fixing tcg_gen_qemu_ld/st call in XCH
>
> changes since v4
> 1. target is now defined as big endian in order to optimize
> push_ret/pop_ret
> 2. all style warnings are fixed
> 3. adding cpu_set/get_sreg functions
> 4. simplifying gen_goto_tb as there is no real paging
> 5. env->pc -> env->pc_w
> 6. making flag dump more compact
> 7. more spacing
> 8. renaming CODE/DATA_INDEX -> MMU_CODE/DATA_IDX
> 9. removing avr_set_feature
> 10. SPL/SPH set bug fix
> 11. switching stb_phys to cpu_stb_data
> 12. cleaning up avr_decode
> 13. saving sreg, rampD/X/Y/Z, eind in HW format (savevm)
> 14. saving CPU features (savevm)
>
> changes since v5
> 1. BLD bug fix
> 2. decoder generator is added
>
> chages since v6
> 1. using cpu_get_sreg/cpu_set_sreg in avr_cpu_gdb_read_register/avr_
> cpu_gdb_write_register
> 2. configure the target as little endian because otherwise GDB does not
> work
> 3. fixing and testing gen_push_ret/gen_pop_ret
>
> changes since v7
> 1. folding back v6
> 2. logging at helper_outb and helper_inb are done for non supported yet
> registers only
> 3. MAINTAINERS updated
>
> changes since v8
> 1. removing hw/avr from hw/Makefile.obj as it should not be built for all
> 2. making linux compilable
> 3. testing on
> a. Mac, Apple LLVM version 7.0.0
> b. Ubuntu 12.04, gcc 4.9.2
> c. Fedora 23, gcc 5.3.1
> 4. folding back some patches
> 5. translation bug fixes for ORI, CPI, XOR instructions
> 6. propper handling of cpu register writes though memory
>
> changes since v9
> 1. removing forward declarations of static functions
> 2. disabling debug prints
> 3. switching to case range instead of if else if ...
> 4. LD/ST IN/OUT accessing CPU maintainder registers are not routed to any
> device
> 5. commenst about sample board and sample IO device added
> 6. sample board description is more descriptive now
> 7. memory_region_allocate_system_memory is used to create RAM
> 8. now there are helper_fullrd & helper_fullwr when LD/ST try to access
> registers
>
> changes since v10
> 1. movig back fullwr & fullrd into the commit where outb and inb were
> introduced
> 2. changing tlb_fill function signature
> 3. adding empty line between functions
> 4. adding newline on the last line of the file
> 5. using tb->flags to generae full access ST/LD instructions
> 6. fixing SBRC bug
> 7. folding back 10th commit
> 8. whenever a new file is introduced it's added to Makefile.objs
>
> changes since v11
> 1. updating to v2.7.0-rc
> 2. removing assignment to env->fullacc from gen_intermediate_code
>
> changes since v12
> 1. fixing spacing
> 2. fixing get/put_segment functions
> 3. removing target-avr/machine.h file
> 4. VMSTATE_SINGLE_TEST -> VMSTATE_SINGLE
> 5. comment spelling
> 6. removing hw/avr/sample_io.c
> 7. char const* -> const char*
> 8. proper ram allocation
> 9. fixing breakpoint functionality.
> 10.env1 -> env
> 11.fixing avr_cpu_gdb_write_register & avr_cpu_gdb_read_register functions
> 12.any cpu is removed
> 12.feature bits are not saved into vm state
>
> changes since v13
> 1. rebasing to v2.7.0-rc1
>
> changes since v14
> 1. I made self review with git gui tool. (I did not know such a thing
> exists)
> 2. removing all 

Re: [PATCH v36 00/17] QEMU AVR 8 bit cores

2019-11-25 Thread Aleksandar Markovic
On Sunday, November 24, 2019, Michael Rolnik  wrote:

> This series of patches adds 8bit AVR cores to QEMU.
> All instruction, except BREAK/DES/SPM/SPMX, are implemented. Not fully
> tested yet.
> However I was able to execute simple code with functions. e.g fibonacci
> calculation.
> This series of patches include a non real, sample board.
> No fuses support yet. PC is set to 0 at reset.
>
>
Michael,

Please, in the next version, add or clean up licence preambles in ALL added
files. It looks the most suitable license for you is LPGL 2.1 with "or
later (at your option)" wording, like you already have in some (but not
all) files, but it is your choice. If possible, make it consistent
throughout the series. Sarah indicated to me she agreed with GPL-like
license, but she will certainly have the chance to speak up if something is
not right in her view. Don't misspell her name (as I did in one of my
responses). All this license thing is important so that one more item of
the series is resolved, and after that you don't need to think about it
anymore.

Regards,
Aleksandar



> the patches include the following
> 1. just a basic 8bit AVR CPU, without instruction decoding or translation
> 2. CPU features which allow define the following 8bit AVR cores
>  avr1
>  avr2 avr25
>  avr3 avr31 avr35
>  avr4
>  avr5 avr51
>  avr6
>  xmega2 xmega4 xmega5 xmega6 xmega7
> 3. a definition of sample machine with SRAM, FLASH and CPU which allows to
> execute simple code
> 4. encoding for all AVR instructions
> 5. interrupt handling
> 6. helpers for IN, OUT, SLEEP, WBR & unsupported instructions
> 7. a decoder which given an opcode decides what istruction it is
> 8. translation of AVR instruction into TCG
> 9. all features together
>
> changes since v3
> 1. rampD/X/Y/Z registers are encoded as 0x00ff (instead of 0x00ff)
> for faster address manipulaton
> 2. ffs changed to ctz32
> 3. duplicate code removed at avr_cpu_do_interrupt
> 4. using andc instead of not + and
> 5. fixing V flag calculation in varios instructions
> 6. freeing local variables in PUSH
> 7. tcg_const_local_i32 -> tcg_const_i32
> 8. using sextract32 instead of my implementation
> 9. fixing BLD instruction
> 10.xor(r) instead of 0xff - r at COM
> 11.fixing MULS/MULSU not to modify inputs' content
> 12.using SUB for NEG
> 13.fixing tcg_gen_qemu_ld/st call in XCH
>
> changes since v4
> 1. target is now defined as big endian in order to optimize
> push_ret/pop_ret
> 2. all style warnings are fixed
> 3. adding cpu_set/get_sreg functions
> 4. simplifying gen_goto_tb as there is no real paging
> 5. env->pc -> env->pc_w
> 6. making flag dump more compact
> 7. more spacing
> 8. renaming CODE/DATA_INDEX -> MMU_CODE/DATA_IDX
> 9. removing avr_set_feature
> 10. SPL/SPH set bug fix
> 11. switching stb_phys to cpu_stb_data
> 12. cleaning up avr_decode
> 13. saving sreg, rampD/X/Y/Z, eind in HW format (savevm)
> 14. saving CPU features (savevm)
>
> changes since v5
> 1. BLD bug fix
> 2. decoder generator is added
>
> chages since v6
> 1. using cpu_get_sreg/cpu_set_sreg in avr_cpu_gdb_read_register/avr_
> cpu_gdb_write_register
> 2. configure the target as little endian because otherwise GDB does not
> work
> 3. fixing and testing gen_push_ret/gen_pop_ret
>
> changes since v7
> 1. folding back v6
> 2. logging at helper_outb and helper_inb are done for non supported yet
> registers only
> 3. MAINTAINERS updated
>
> changes since v8
> 1. removing hw/avr from hw/Makefile.obj as it should not be built for all
> 2. making linux compilable
> 3. testing on
> a. Mac, Apple LLVM version 7.0.0
> b. Ubuntu 12.04, gcc 4.9.2
> c. Fedora 23, gcc 5.3.1
> 4. folding back some patches
> 5. translation bug fixes for ORI, CPI, XOR instructions
> 6. propper handling of cpu register writes though memory
>
> changes since v9
> 1. removing forward declarations of static functions
> 2. disabling debug prints
> 3. switching to case range instead of if else if ...
> 4. LD/ST IN/OUT accessing CPU maintainder registers are not routed to any
> device
> 5. commenst about sample board and sample IO device added
> 6. sample board description is more descriptive now
> 7. memory_region_allocate_system_memory is used to create RAM
> 8. now there are helper_fullrd & helper_fullwr when LD/ST try to access
> registers
>
> changes since v10
> 1. movig back fullwr & fullrd into the commit where outb and inb were
> introduced
> 2. changing tlb_fill function signature
> 3. adding empty line between functions
> 4. adding newline on the last line of the file
> 5. using tb->flags to generae full access ST/LD instructions
> 6. fixing SBRC bug
> 7. folding back 10th commit
> 8. whenever a new file is introduced it's added to Makefile.objs
>
> changes since v11
> 1. updating to v2.7.0-rc
> 2. removing assignment to env->fullacc from gen_intermediate_code
>
> changes since v12
> 1. fixing spacing
> 2. fixing get/put_segment functions
> 3. removing target-avr/machine.h file
> 

Re: [PATCH v36 00/17] QEMU AVR 8 bit cores

2019-11-25 Thread Aleksandar Markovic
On Sunday, November 24, 2019, Michael Rolnik  wrote:

> This series of patches adds 8bit AVR cores to QEMU.
> All instruction, except BREAK/DES/SPM/SPMX, are implemented. Not fully
> tested yet.
> However I was able to execute simple code with functions. e.g fibonacci
> calculation.
> This series of patches include a non real, sample board.
> No fuses support yet. PC is set to 0 at reset.
>
> the patches include the following
> 1. just a basic 8bit AVR CPU, without instruction decoding or translation
> 2. CPU features which allow define the following 8bit AVR cores
>  avr1
>  avr2 avr25
>  avr3 avr31 avr35
>  avr4
>  avr5 avr51
>  avr6
>  xmega2 xmega4 xmega5 xmega6 xmega7
> 3. a definition of sample machine with SRAM, FLASH and CPU which allows to
> execute simple code
> 4. encoding for all AVR instructions
> 5. interrupt handling
> 6. helpers for IN, OUT, SLEEP, WBR & unsupported instructions
> 7. a decoder which given an opcode decides what istruction it is
> 8. translation of AVR instruction into TCG
> 9. all features together
>
>
Michael,

Please do persist.

In next version, please add to the cover letter, right at this place:

1) An example of invoking QEMU for AVR, and doing some simple stuff with
such virtual machine

2) An example of debugging QEMU-powered AVR vurtual machine with GDB

3) (optional) Some other interesting example.

This is needed so that more people get interested in your series, try the
things out, convince themself in the value of this series (without digging
into individual patches searching fir examples).

Regards,
Aleksandar


> changes since v3
> 1. rampD/X/Y/Z registers are encoded as 0x00ff (instead of 0x00ff)
> for faster address manipulaton
> 2. ffs changed to ctz32
> 3. duplicate code removed at avr_cpu_do_interrupt
> 4. using andc instead of not + and
> 5. fixing V flag calculation in varios instructions
> 6. freeing local variables in PUSH
> 7. tcg_const_local_i32 -> tcg_const_i32
> 8. using sextract32 instead of my implementation
> 9. fixing BLD instruction
> 10.xor(r) instead of 0xff - r at COM
> 11.fixing MULS/MULSU not to modify inputs' content
> 12.using SUB for NEG
> 13.fixing tcg_gen_qemu_ld/st call in XCH
>
> changes since v4
> 1. target is now defined as big endian in order to optimize
> push_ret/pop_ret
> 2. all style warnings are fixed
> 3. adding cpu_set/get_sreg functions
> 4. simplifying gen_goto_tb as there is no real paging
> 5. env->pc -> env->pc_w
> 6. making flag dump more compact
> 7. more spacing
> 8. renaming CODE/DATA_INDEX -> MMU_CODE/DATA_IDX
> 9. removing avr_set_feature
> 10. SPL/SPH set bug fix
> 11. switching stb_phys to cpu_stb_data
> 12. cleaning up avr_decode
> 13. saving sreg, rampD/X/Y/Z, eind in HW format (savevm)
> 14. saving CPU features (savevm)
>
> changes since v5
> 1. BLD bug fix
> 2. decoder generator is added
>
> chages since v6
> 1. using cpu_get_sreg/cpu_set_sreg in avr_cpu_gdb_read_register/avr_
> cpu_gdb_write_register
> 2. configure the target as little endian because otherwise GDB does not
> work
> 3. fixing and testing gen_push_ret/gen_pop_ret
>
> changes since v7
> 1. folding back v6
> 2. logging at helper_outb and helper_inb are done for non supported yet
> registers only
> 3. MAINTAINERS updated
>
> changes since v8
> 1. removing hw/avr from hw/Makefile.obj as it should not be built for all
> 2. making linux compilable
> 3. testing on
> a. Mac, Apple LLVM version 7.0.0
> b. Ubuntu 12.04, gcc 4.9.2
> c. Fedora 23, gcc 5.3.1
> 4. folding back some patches
> 5. translation bug fixes for ORI, CPI, XOR instructions
> 6. propper handling of cpu register writes though memory
>
> changes since v9
> 1. removing forward declarations of static functions
> 2. disabling debug prints
> 3. switching to case range instead of if else if ...
> 4. LD/ST IN/OUT accessing CPU maintainder registers are not routed to any
> device
> 5. commenst about sample board and sample IO device added
> 6. sample board description is more descriptive now
> 7. memory_region_allocate_system_memory is used to create RAM
> 8. now there are helper_fullrd & helper_fullwr when LD/ST try to access
> registers
>
> changes since v10
> 1. movig back fullwr & fullrd into the commit where outb and inb were
> introduced
> 2. changing tlb_fill function signature
> 3. adding empty line between functions
> 4. adding newline on the last line of the file
> 5. using tb->flags to generae full access ST/LD instructions
> 6. fixing SBRC bug
> 7. folding back 10th commit
> 8. whenever a new file is introduced it's added to Makefile.objs
>
> changes since v11
> 1. updating to v2.7.0-rc
> 2. removing assignment to env->fullacc from gen_intermediate_code
>
> changes since v12
> 1. fixing spacing
> 2. fixing get/put_segment functions
> 3. removing target-avr/machine.h file
> 4. VMSTATE_SINGLE_TEST -> VMSTATE_SINGLE
> 5. comment spelling
> 6. removing hw/avr/sample_io.c
> 7. char const* -> const char*
> 8. proper ram allocation
> 

Re: [PATCH v36 00/17] QEMU AVR 8 bit cores

2019-11-25 Thread Philippe Mathieu-Daudé

Cc'ing Joaquin who is implementing the ATmega328.

On 11/24/19 6:02 AM, Michael Rolnik wrote:

This series of patches adds 8bit AVR cores to QEMU.
All instruction, except BREAK/DES/SPM/SPMX, are implemented. Not fully tested 
yet.
However I was able to execute simple code with functions. e.g fibonacci 
calculation.
This series of patches include a non real, sample board.
No fuses support yet. PC is set to 0 at reset.

the patches include the following
1. just a basic 8bit AVR CPU, without instruction decoding or translation
2. CPU features which allow define the following 8bit AVR cores
  avr1
  avr2 avr25
  avr3 avr31 avr35
  avr4
  avr5 avr51
  avr6
  xmega2 xmega4 xmega5 xmega6 xmega7
3. a definition of sample machine with SRAM, FLASH and CPU which allows to 
execute simple code
4. encoding for all AVR instructions
5. interrupt handling
6. helpers for IN, OUT, SLEEP, WBR & unsupported instructions
7. a decoder which given an opcode decides what istruction it is
8. translation of AVR instruction into TCG
9. all features together

changes since v3
1. rampD/X/Y/Z registers are encoded as 0x00ff (instead of 0x00ff) for 
faster address manipulaton
2. ffs changed to ctz32
3. duplicate code removed at avr_cpu_do_interrupt
4. using andc instead of not + and
5. fixing V flag calculation in varios instructions
6. freeing local variables in PUSH
7. tcg_const_local_i32 -> tcg_const_i32
8. using sextract32 instead of my implementation
9. fixing BLD instruction
10.xor(r) instead of 0xff - r at COM
11.fixing MULS/MULSU not to modify inputs' content
12.using SUB for NEG
13.fixing tcg_gen_qemu_ld/st call in XCH

changes since v4
1. target is now defined as big endian in order to optimize push_ret/pop_ret
2. all style warnings are fixed
3. adding cpu_set/get_sreg functions
4. simplifying gen_goto_tb as there is no real paging
5. env->pc -> env->pc_w
6. making flag dump more compact
7. more spacing
8. renaming CODE/DATA_INDEX -> MMU_CODE/DATA_IDX
9. removing avr_set_feature
10. SPL/SPH set bug fix
11. switching stb_phys to cpu_stb_data
12. cleaning up avr_decode
13. saving sreg, rampD/X/Y/Z, eind in HW format (savevm)
14. saving CPU features (savevm)

changes since v5
1. BLD bug fix
2. decoder generator is added

chages since v6
1. using cpu_get_sreg/cpu_set_sreg in 
avr_cpu_gdb_read_register/avr_cpu_gdb_write_register
2. configure the target as little endian because otherwise GDB does not work
3. fixing and testing gen_push_ret/gen_pop_ret

changes since v7
1. folding back v6
2. logging at helper_outb and helper_inb are done for non supported yet 
registers only
3. MAINTAINERS updated

changes since v8
1. removing hw/avr from hw/Makefile.obj as it should not be built for all
2. making linux compilable
3. testing on
 a. Mac, Apple LLVM version 7.0.0
 b. Ubuntu 12.04, gcc 4.9.2
 c. Fedora 23, gcc 5.3.1
4. folding back some patches
5. translation bug fixes for ORI, CPI, XOR instructions
6. propper handling of cpu register writes though memory

changes since v9
1. removing forward declarations of static functions
2. disabling debug prints
3. switching to case range instead of if else if ...
4. LD/ST IN/OUT accessing CPU maintainder registers are not routed to any device
5. commenst about sample board and sample IO device added
6. sample board description is more descriptive now
7. memory_region_allocate_system_memory is used to create RAM
8. now there are helper_fullrd & helper_fullwr when LD/ST try to access 
registers

changes since v10
1. movig back fullwr & fullrd into the commit where outb and inb were introduced
2. changing tlb_fill function signature
3. adding empty line between functions
4. adding newline on the last line of the file
5. using tb->flags to generae full access ST/LD instructions
6. fixing SBRC bug
7. folding back 10th commit
8. whenever a new file is introduced it's added to Makefile.objs

changes since v11
1. updating to v2.7.0-rc
2. removing assignment to env->fullacc from gen_intermediate_code

changes since v12
1. fixing spacing
2. fixing get/put_segment functions
3. removing target-avr/machine.h file
4. VMSTATE_SINGLE_TEST -> VMSTATE_SINGLE
5. comment spelling
6. removing hw/avr/sample_io.c
7. char const* -> const char*
8. proper ram allocation
9. fixing breakpoint functionality.
10.env1 -> env
11.fixing avr_cpu_gdb_write_register & avr_cpu_gdb_read_register functions
12.any cpu is removed
12.feature bits are not saved into vm state

changes since v13
1. rebasing to v2.7.0-rc1

changes since v14
1. I made self review with git gui tool. (I did not know such a thing exists)
2. removing all double/tripple spaces
3. removing comment reference to SampleIO
4. folding back some changes, so there is not deleted lines in my code
5. moving avr configuration, within configure file, before chris

changes since v15
1. removing IO registers cache from CPU
2. implementing CBI/SBI as read(helper_inb), modify, write(helper_outb)
3. implementing CBIC/SBIC as 

[PATCH v36 00/17] QEMU AVR 8 bit cores

2019-11-23 Thread Michael Rolnik
This series of patches adds 8bit AVR cores to QEMU.
All instruction, except BREAK/DES/SPM/SPMX, are implemented. Not fully tested 
yet.
However I was able to execute simple code with functions. e.g fibonacci 
calculation.
This series of patches include a non real, sample board.
No fuses support yet. PC is set to 0 at reset.

the patches include the following
1. just a basic 8bit AVR CPU, without instruction decoding or translation
2. CPU features which allow define the following 8bit AVR cores
 avr1
 avr2 avr25
 avr3 avr31 avr35
 avr4
 avr5 avr51
 avr6
 xmega2 xmega4 xmega5 xmega6 xmega7
3. a definition of sample machine with SRAM, FLASH and CPU which allows to 
execute simple code
4. encoding for all AVR instructions
5. interrupt handling
6. helpers for IN, OUT, SLEEP, WBR & unsupported instructions
7. a decoder which given an opcode decides what istruction it is
8. translation of AVR instruction into TCG
9. all features together

changes since v3
1. rampD/X/Y/Z registers are encoded as 0x00ff (instead of 0x00ff) for 
faster address manipulaton
2. ffs changed to ctz32
3. duplicate code removed at avr_cpu_do_interrupt
4. using andc instead of not + and
5. fixing V flag calculation in varios instructions
6. freeing local variables in PUSH
7. tcg_const_local_i32 -> tcg_const_i32
8. using sextract32 instead of my implementation
9. fixing BLD instruction
10.xor(r) instead of 0xff - r at COM
11.fixing MULS/MULSU not to modify inputs' content
12.using SUB for NEG
13.fixing tcg_gen_qemu_ld/st call in XCH

changes since v4
1. target is now defined as big endian in order to optimize push_ret/pop_ret
2. all style warnings are fixed
3. adding cpu_set/get_sreg functions
4. simplifying gen_goto_tb as there is no real paging
5. env->pc -> env->pc_w
6. making flag dump more compact
7. more spacing
8. renaming CODE/DATA_INDEX -> MMU_CODE/DATA_IDX
9. removing avr_set_feature
10. SPL/SPH set bug fix
11. switching stb_phys to cpu_stb_data
12. cleaning up avr_decode
13. saving sreg, rampD/X/Y/Z, eind in HW format (savevm)
14. saving CPU features (savevm)

changes since v5
1. BLD bug fix
2. decoder generator is added

chages since v6
1. using cpu_get_sreg/cpu_set_sreg in 
avr_cpu_gdb_read_register/avr_cpu_gdb_write_register
2. configure the target as little endian because otherwise GDB does not work
3. fixing and testing gen_push_ret/gen_pop_ret

changes since v7
1. folding back v6
2. logging at helper_outb and helper_inb are done for non supported yet 
registers only
3. MAINTAINERS updated

changes since v8
1. removing hw/avr from hw/Makefile.obj as it should not be built for all
2. making linux compilable
3. testing on
a. Mac, Apple LLVM version 7.0.0
b. Ubuntu 12.04, gcc 4.9.2
c. Fedora 23, gcc 5.3.1
4. folding back some patches
5. translation bug fixes for ORI, CPI, XOR instructions
6. propper handling of cpu register writes though memory

changes since v9
1. removing forward declarations of static functions
2. disabling debug prints
3. switching to case range instead of if else if ...
4. LD/ST IN/OUT accessing CPU maintainder registers are not routed to any device
5. commenst about sample board and sample IO device added
6. sample board description is more descriptive now
7. memory_region_allocate_system_memory is used to create RAM
8. now there are helper_fullrd & helper_fullwr when LD/ST try to access 
registers

changes since v10
1. movig back fullwr & fullrd into the commit where outb and inb were introduced
2. changing tlb_fill function signature
3. adding empty line between functions
4. adding newline on the last line of the file
5. using tb->flags to generae full access ST/LD instructions
6. fixing SBRC bug
7. folding back 10th commit
8. whenever a new file is introduced it's added to Makefile.objs

changes since v11
1. updating to v2.7.0-rc
2. removing assignment to env->fullacc from gen_intermediate_code

changes since v12
1. fixing spacing
2. fixing get/put_segment functions
3. removing target-avr/machine.h file
4. VMSTATE_SINGLE_TEST -> VMSTATE_SINGLE
5. comment spelling
6. removing hw/avr/sample_io.c
7. char const* -> const char*
8. proper ram allocation
9. fixing breakpoint functionality.
10.env1 -> env
11.fixing avr_cpu_gdb_write_register & avr_cpu_gdb_read_register functions
12.any cpu is removed
12.feature bits are not saved into vm state

changes since v13
1. rebasing to v2.7.0-rc1

changes since v14
1. I made self review with git gui tool. (I did not know such a thing exists)
2. removing all double/tripple spaces
3. removing comment reference to SampleIO
4. folding back some changes, so there is not deleted lines in my code
5. moving avr configuration, within configure file, before chris

changes since v15
1. removing IO registers cache from CPU
2. implementing CBI/SBI as read(helper_inb), modify, write(helper_outb)
3. implementing CBIC/SBIC as read(helper_inb), check, branch
4. adding missing tcg_temp_free_i32 for tcg_const_i32

changes since v16
1.