Commit Graph

129 Commits (5fb9b50da8f1e02fa0c81ee43d7961c479ef5f12)

Author SHA1 Message Date
Ming Yue 09a2c0b324
Remove exception loop tags. (#457) 3 years ago
Ming Yue 25d180a09b
Use a dedicated symbol for in-function loop to avoid the weak symbol JAL range error when a strong symbol is defined outside. (#455) 3 years ago
Gaurav-Aggarwal-AWS d5a10e4595
Add alignment for the direct mode handler (#449)
It is still possible to further relax the alignment using linker script
if needed.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav-Aggarwal-AWS cf248aec2d
Add support for 16 MPU regions to GCC Cortex-M33 ports (#448)
* Add support for 16 MPU regions to GCC Cortex-M33 TZ port

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Add support for 16 MPU regions to Cortex-M33 NTZ GCC port

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav-Aggarwal-AWS 9efca75d1e
Riscv re-factoring (#444)
* Refactor RISCV port

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Changes to make re-factoring work on ESP32-C3

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Remove alignment and place handlers in separate sections

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Correct section names

This is needed so that the assemblers correctly recognizes functions.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Move mtvec programming to the application

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Refactor mtimer udpate code

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Move critical nesting to port layer

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Respect configTASK_RETURN_ADDRESS

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>

* Formatting changes

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Ming Yue 043c2c7ef6
Fix GCC/RX100 function naming error. (#440) 3 years ago
Amit Tomar c13719d2d0
fix alignment exception for ullPortInterruptNesting. (#317)
* fix alignment exception for ullPortInterruptNesting.

While loading (LDR X5, ullPortInterruptNestingConst) the ullPortInterruptNesting
variable, the program control seems to be stuck and there is no abort or stack
trace observed (as there is no exception handler is installed to catch unaligned
access exception).

Program control moves forward, if one just declares this varible to be 2 bytes
aligned but then varible is not updated properly.

One of my colleague, pointed out that issue is due to the fact that
ullPortInterruptNesting must be at 8 bytes aligned address but since
"vApplicationIRQHandler" (that has 4 bytes of address) is sitting between
two 8 bytes aligned addresses that forces ullPortInterruptNesting to be at
4 byte aligned address, causing all sort of mess.

It works on QEMU (on ARM64) as it is, since there is no such check for
unaligned access but on real hardware it is prohibited.

Workaround to this problem is, either we skip 4 byets (using .align 4) after
vApplicationIRQHandler declaration or declare it the end of all declarations.
This commit does the latter one.

Signed-off-by: Amit Singh Tomar <atomar25opensource@gmail.com>

* Update portASM.S

Remove 1 tab = 4 spaces

Co-authored-by: Amit Singh Tomar <atomar25opensource@gmail.com>
Co-authored-by: alfred gedeon <28123637+alfred2g@users.noreply.github.com>
Co-authored-by: Joseph Julicher <jjulicher@mac.com>
3 years ago
Fabian 481c722ef3
RISC-V: No #error on RV64 regarding byte alignment (#367)
Co-authored-by: Joseph Julicher <jjulicher@mac.com>
Co-authored-by: Gaurav-Aggarwal-AWS <33462878+aggarg@users.noreply.github.com>
3 years ago
leona 81d15dc550
Fix: Interrut Handler Register Function and Exception Process (#41)
Signed-off-by: shiode <shiode@aptpod.co.jp>

Co-authored-by: Cobus van Eeden <35851496+cobusve@users.noreply.github.com>
Co-authored-by: David Chalco <59750547+dachalco@users.noreply.github.com>
Co-authored-by: Joseph Julicher <jjulicher@mac.com>
3 years ago
Gaurav Aggarwal 44fc137428 Add option to disable unprivileged critical sections
This commit introduces a new config
configALLOW_UNPRIVILEGED_CRITICAL_SECTIONS which enables developers to
prevent critical sections from unprivileged tasks. It defaults to 1 for
backward compatibility. Application should set it to 0 to disable
critical sections from unprivileged tasks.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav Aggarwal 7a3848753b Change xPortRaisePrivilege and vPortResetPrivilege to macros
This prevents non-kernel code from calling these functions.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav-Aggarwal-AWS 06fb777e43
Update comments for the ARM_CA53_64_BIT_SRE port (#403)
Mention that FreeRTOS_IRQ_Handler should not be used for FIQs and the
reason for assuming Group 1 for Interrupt Acknowledge and End Of
Interrupt registers.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Stephane Viau 68ddb32b55
Handle interrupt acknowledge register in Cortex-A53 SRE port (#392)
Let the FreeRTOS IRQ handler properly store and restore the ICCIAR
register value around the vApplicationIRQHandler() call.

Signed-off-by: Stephane Viau <stephane.viau@oss.nxp.com>

Co-authored-by: Stephane Viau <stephane.viau@oss.nxp.com>
Co-authored-by: Gaurav-Aggarwal-AWS <33462878+aggarg@users.noreply.github.com>
3 years ago
swaldhoer a030d0a02b
fix typo (#399) 3 years ago
Gaurav-Aggarwal-AWS 1b86b39940
Remove AVR ports from main repo (#394)
These ports now exist in the
https://github.com/FreeRTOS/FreeRTOS-Kernel-Partner-Supported-Ports repo.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav Aggarwal 99a5a5fe82 Fix free secure context for Cortex-M23 ports
Update the branching condition to correctly free secure context when
there is one.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav Aggarwal 06ea7275b3 Implement secure stack sealing as per ARM's recommendation
Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav Aggarwal 61f7560243 Associate secure context with task handle
The secure side context management code now checks that the secure
context being saved or restored belongs to the task being switched-out
or switched-in respectively.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav Aggarwal ccaa0f4d6e Pre-allocate secure-side context structures
This commit improves ARMv8-M security by pre-allocating secure-side task
context structures and changing how tasks reference a secure-side
context structure when calling a secure function. The new configuration
constant secureconfigMAX_SECURE_CONTEXTS sets the number of secure
context structures to pre-allocate. secureconfigMAX_SECURE_CONTEXTS
defaults to 8 if left undefined.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Gaurav-Aggarwal-AWS fa0f5c436c
Add freertos_risc_v_chip_specific_extensions.h for 64-bit ports (#385)
* Add freertos_risc_v_chip_specific_extensions.h for 64-bit ports

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
3 years ago
Kristine Jassmann b5a9229563
Warning fixes. (#356)
* Use cast to fix warnings.

* Remove all empty definitions of portCLEAN_UP_TCB( pxTCB ) and
  portALLOCATE_SECURE_CONTEXT( ulSecureStackSize ) from ports.
  When these are undefined, the default empty definition is defined
  in FreeRTOS.h.
4 years ago
swaldhoer 46338705bd
Replace two dashes and one whitespace with their corresponding ASCII characters. (#362) 4 years ago
Gaurav-Aggarwal-AWS 4e3bf0f5c0
Add Cortex-A53 port with system register interface for CPU interface access (#357)
The difference between this port and portable/GCC/ARM_CA53_64_BIT is
that this port uses System Register interface to access CPU interface
while the other one uses Memory-mapped interface.

Signed-off-by: Gaurav Aggarwal 
Co-authored-by: Cobus van Eeden <35851496+cobusve@users.noreply.github.com>
4 years ago
Paul Bartell eec42331b4 Normalize files with mixed line endings (introduced in commit 3a413d1) 4 years ago
Paul Bartell 3a413d1022 Add SPDX-License-Identifier: MIT to MIT licensed files. 4 years ago
Paul Bartell b286f173e8 Update license text for ports that were previously missed. 4 years ago
Paul Bartell e31dccae80 Remove "1 tab == 4 spaces!" line from files that still contain it. 4 years ago
Paul Bartell adfc53368f Update copyright year from 2020 to 2021 4 years ago
Paul Bartell 08dc6f64ee Change kernel revision in each file header from V10.4.3 to <DEVELOPMENT BRANCH> 4 years ago
Joseph Julicher 736f2302ae
deprecating the mcf5235 port (#334) 4 years ago
j4cbo f37bcd5c14
Wrap macros in do { ... } while( 0 ) (#240) 4 years ago
Tobias Schulte cb7bef09f2
Adjust portPOINTER_SIZE_TYPE to correct size (#275)
* Adjust portPOINTER_SIZE_TYPE to correct size

portPOINTER_SIZE_TYPE wasn't yet set correctly to be 16 bit

* Fixed FreeRTOS file header to comply with automatic checks

Co-authored-by: Cobus van Eeden <35851496+cobusve@users.noreply.github.com>
4 years ago
Cobus van Eeden ec62f69dab [AUTO][RELEASE]: Bump file header version to "10.4.3" 4 years ago
David Chalco 337bca615e [AUTO][RELEASE]: Bump file header version to "10.4.2" 4 years ago
Gaurav-Aggarwal-AWS ebbe2cf854
Ensure interrupts are enabled at first task start (#214)
Critical sections in FreeRTOS are implemented using the following two
functions:

void vPortEnterCritical( void )
{
    portDISABLE_INTERRUPTS();
    uxCriticalNesting++;
}

void vPortExitCritical( void )
{
    uxCriticalNesting--;

    if( uxCriticalNesting == 0 )
    {
        portENABLE_INTERRUPTS();
    }
}

uxCriticalNesting is initialized to a large value at the start and set
to zero when the scheduler is started (xPortStartScheduler). As a
result, before the scheduler is started, a pair of enter/exit critical
section will leave the interrupts disabled because uxCriticalNesting
will not reach zero in the vPortExitCritical function. This is done to
ensure that the interrupts remain disabled from the time first FreeRTOS
API is called to the time when the scheduler is started. The scheduler
starting code is expected to enure that interrupts are enabled before
the first task starts executing.

Cortex-M33 ports were not enabling interrupts before starting the first
task and as a result, the first task was started with interrupts
disabled. This PR fixes the issue by ensuring that interrupts are
enabled before the first task is started.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
4 years ago
Jon Snow bdb38d85dc
update interrupt vector names for ATMega32 (#196) 4 years ago
NoMaY (a user of Japan.RenesasRulz.com) c3117b4237
Maintenance: Add readme.txt in each Renesas RX folder to show recommended port (#152)
* Maintenance: Add readme.txt in each Renesas RX folder to show recomended port
* Update readme.txt in each Renesas RX folder regarding to Notes *1 and *2 (both are RX100 port)
4 years ago
alfred gedeon d428209d01
Fix some broken/redirected URL (#172)
* Style: fix some broken/redirect links

* Fix: atmel url

* Fix microchip typo

* Fix url links

* Fix shortcut link

* Comment: fix line wrapping

* Style: fix line wrapping to 80 chars

* Add now microchip beside Atmel

* Fix link in History

* Add Now Microchip before Atmel link

* Comment: add *
4 years ago
Cobus van Eeden 385e700953
Update History.txt and fix versioning in asm files (#177) 4 years ago
David Chalco 3604527e3b
Update version number to 10.4.1 (#173) 4 years ago
NoMaY (a user of Japan.RenesasRulz.com) 242808132c
Fix broken #warning message in ARM_CMx_MPU/portmacro.h between 10.3.1 and 10.4.0 (#171) 4 years ago
RichardBarry 85768bb3e0
Sets the version number to 10.4.0 in assembly files. The (#166)
assembly files were missed when the other source files had
their version numbers updated.
4 years ago
David Chalco 5dfab0306b
Update version number to 10.4.0 (#153) 4 years ago
Joseph Julicher 2f14899ce8
Revert "RISC-V: Add RV32E / FPU support for GCC (#140)" (#163)
This reverts commit 0037a6c574.
4 years ago
Emmanuel Puerto 0037a6c574
RISC-V: Add RV32E / FPU support for GCC (#140)
* Change vPortSetupTimerInterrupt in order to have 64bits access on rv64

* Support RV32E - RISC-V architecture (GCC)

Signed-off-by: Emmanuel Puerto <emmanuel.puerto@sifive.com>

* Support FPU - RISC-V architecture (GCC)

Signed-off-by: Emmanuel Puerto <emmanuel.puerto@sifive.com>

* Fix interrupt managment and FPU initialization
4 years ago
alfred gedeon 148c81a7bc
Revert "Fix: Add Parenthesis around if-statement in macro (#138)" (#148)
This reverts commit 45e97bd246.
5 years ago
Ming Yue 58ffcb1a6d
Revert "Fix race condition when tracing is enabled (#95)" (#149)
This reverts commit 61635d5b8b.
5 years ago
alfred gedeon 45e97bd246
Fix: Add Parenthesis around if-statement in macro (#138)
Co-authored-by: Alfred Gedeon <gedeonag@amazon.com>
5 years ago
Ravishankar Bhagavandas 1d8df4752e
Update Renesas GCC compiler ports (#135)
* Add RX200 GCC compiler

Signed-off-by: Dinh Van Nam <vannam.dinh.xt@renesas.com>

* Update GCC compiler for:
 * RX600v2
 * RX600
 * RX100

Signed-off-by: Dinh Van Nam <vannam.dinh.xt@renesas.com>

* Use configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H flag

* Use configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H flag RX100, RX200

Co-authored-by: Dinh Van Nam <vannam.dinh.xt@renesas.com>
5 years ago
alfred gedeon a038146915
Style: Make freertos.org = FreeRTOS.org and add https (#134)
* Style: make freertos.org = FreeRTOS.org also add https

* Style: Fix freertos into FreeRTOS

* Style: Fix freertos into FreeRTOS

Co-authored-by: Alfred Gedeon <gedeonag@amazon.com>
5 years ago
alfred gedeon 0b0a2060c0
Style: Change FreeRTOS websites in comments (#131)
* Style: Change FreeRTOS websites in comments

* Style: Change freertos to FreeRTOS in comments

* Style: Remove broken link

Co-authored-by: Alfred Gedeon <gedeonag@amazon.com>
5 years ago
Joseph Julicher 386d854e0b
added a warning concerning the incomplete testing of the RX700v3_DFPU port (#124) 5 years ago
alfred gedeon 8c77117c32
Style: Remove tabs and tab == 4 spaces (#120)
* Style: Remove tabls and tab == 4 spaces

* Style: remove xx accidentally left

* Style: revert uncrustify for untested portable directories

* Style: revert more uncrustify files

* Style: Revert more uncrustified files

* Style: Revert some uncrutified files

* Style: change more files

* Style: remove t tab == 4 spaces

* Style: remove tabs = spaces

* Style: revert changed files

* Style: redo the stuyles

* Style: add uncrustify disable parsing for asm

Co-authored-by: Alfred Gedeon <gedeonag@amazon.com>
5 years ago
alfred gedeon 86653e2a1f
Style: Revert uncrustify for portable directories (#122)
* Style: revert uncrustify portable directories

* Style: Uncrustify Some Portable files

Co-authored-by: Alfred Gedeon <gedeonag@amazon.com>
5 years ago
NoMaY (a user of Japan.RenesasRulz.com) a6da1cd0ce
Add Renesas RXv3 port layer supporting RXv3's double precision FPU (#104) 5 years ago
Simon Beaudoin 61635d5b8b
Fix race condition when tracing is enabled (#95)
* Update port.c

I discovered a very snicky and tricky race condition scenario when integrating tracealyzer code into our project.

A little background  on CortexR5 : When the IRQ line (comming from the interrupt controller, to which every peripheral IRQ lines connect) of the processor rises and the IRQ Enable bit in the status register of the CPU permits it, the CPU traps into interrupt mode. Several things happen. First, the CPU finishes the instruction it was performing. Second, it places the content of the CPSR register into the SPSR_irq register. And third, the mode of the CPU is changed to IRQ_Mode and /!\ THE IRQ ENABLE BIT IN CPSR_irq IS AUTOMATICALLY CLEARED /!\. The reason is to ensure that upon landing into IRQ code, we find ourselves automatically in a critical section because we cannot be interrupted again because the bit is cleared. The programmer can, if he wants, re-enable IRQs inside IRQ code itself to allow interrupt nesting. But it has to be wanted and meditated. 


Now, inside portASM.S, at the end of 'FreeRTOS_IRQ_Handler' assembly function, a call to 'vTaskSwitchContextConst' is made if the variable 'ulPortYieldRequired' was set by someone while executing the interrupt. Before branching to that function, a 'CPSID	i' instruction was placed to ensure that interrupts are disabled in case someone re-enabled it. Inside 'vTaskSwitchContext', there is the macro 'traceTASK_SWITCHED_OUT' that gets populated when tracing is enabled. 

The bug is right there.. If the macro is populated and inside that macro there is a matching call to 'ulPortSetInterruptMask' and 'vPortClearInterruptMask', a race condition can occure is there is a OS Tick timer interrupt waiting at the interrupt controller's door. Upon calling 'vTaskSwitchContext', the interrupts are not masked in the interrupt controller, the only barrier against the CPU servicing that tick interrupt while already performing the function is that the IRQ Enable bit cleared. 'ulPortSetInterruptMask' 
does what's its supposed to do, but doesn't take into account the IRQ Enable bit in CPSR. Wheter or not the bit was cleared, the function sets it at the end. When calling the matching 'vPortClearInterruptMask', the function clears the interrupt mask in the interrupt controller. Because the IRQ Enable bit (that was cleared) has been set no matter what in 'ulPortSetInterruptMask', the CPU services the OS Tick Interrupt right away. 

The bug is there : instead of completing the 'vTaskSwitchContext' function, the CPU re-enters the switch context path right after 'traceTASK_SWITCHED_OUT' thus corrupting the CPU state and eventually triggering either an undefined instruction, data or instruction abort.

* Update port.c

Error on my part, this is the right inline asm code to retreive CPSR register

* Update port.c

Forgot an * while writing comment..
5 years ago
Gaurav-Aggarwal-AWS 287361091b
Allow application to override TEX,S,C and B bits for Flash and RAM (#113)
The TEX,  Shareable (S), Cacheable (C) and Bufferable (B) bits define
the memory type, and where necessary the cacheable and shareable
properties of the memory region.

The default values for these bits, as configured in our MPU ports, are
sometimes not suitable for application. One such example is when the MCU
has a cache, the application writer may not want to mark the memory as
shareable to avoid disabling the cache. This change allows the
application writer to override default vales for TEX, S C and B bits for
Flash and RAM in their FreeRTOSConfig.h. The following two new
configurations are introduced:

- configTEX_S_C_B_FLASH
- configTEX_S_C_B_SRAM

If undefined, the default values for the above configurations are
TEX=000, S=1, C=1, B=1. This ensures backward compatibility.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
m17336 a2e00f0c6b
Update to AVR_Mega0 and AVR_Dx GCC ports + addition of their IAR equivalents (#106)
* Removed TICK_stop() macro from portable/GCC/{AVR_AVRDx, AVR_Mega0}/porthardware.h because it is not used anywhere.

* Updated indentation in portable/GCC/{AVR_AVRDx, AVR_Mega0}/* files.

* Added portable/IAR/{AVR_AVRDx, AVR_Mega0 folders.
5 years ago
Gaurav-Aggarwal-AWS 676d99e302
Use configSYSTICK_CLOCK_HZ to configure SysTick (#103)
configSYSTICK_CLOCK_HZ should be used to configure SysTick to support
the use case when the clock for SysTick timer is scaled from the main
CPU clock.

configSYSTICK_CLOCK_HZ is defined to configCPU_CLOCK_HZ when it is not
defined in FreeRTOSConfig.h.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
Gaurav-Aggarwal-AWS 7dd6b76011
Add support for 16 MPU regions to Cortex-M4 MPU ports (#96)
ARMv7-M supports 8 or 16 MPU regions. FreeRTOS Cortex-M4 MPU ports so
far assumed 8 regions. This change adds support for 16 MPU regions. The
hardware with 16 MPU regions must define configTOTAL_MPU_REGIONS to 16
in their FreeRTOSConfig.h.

If left undefined, it defaults to 8 for backward compatibility.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
m17336 bb56edff2f
Added GCC port files for AVR Mega0 and AVR Dx. (#101) 5 years ago
Gaurav-Aggarwal-AWS 149f06c70f
Update incorrect port in comments (#87)
Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
Gaurav-Aggarwal-AWS a717d9c62b
Update portNVIC_SYSPRI2_REG to portNVIC_SHPR3_REG (#86)
The reason for the change is that the register is called System Handler
Priority Register 3 (SHPR3).

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
Gaurav-Aggarwal-AWS bb1c429378
Place privileged symbols correctly (#84)
Some of the privileged symbols were not being placed in their respective
sections. This commit addresses those and places them in
privileged_functions or privileged_data section.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
Gaurav-Aggarwal-AWS b6a43866da
Add support for privileged heap to ARMV8-M ports (#85)
If xTaskCreate API is used to create a task, the task's stack is
allocated on heap using pvPortMalloc. This places the task's stack
in the privileged data section, if the heap is placed in the
privileged data section.

We use a separate MPU region to grant a task access to its stack.
If the task's stack is in the privileged data section, this results in
overlapping MPU regions as privileged data section is already protected
using a separate MPU region. ARMv8-M does not allow overlapping MPU
regions and this results in a fault. This commit ensures to not use a
separate MPU region for the task's stack if it lies within the
privileged data section.

Note that if the heap memory is placed in the privileged data section,
the xTaskCreate API cannot be used to create an unprivileged task as
the task's stack will be in the privileged data section and the task
won't have access to it. xTaskCreateRestricted and
xTaskCreateRestrictedStatic API should be used to create unprivileged
tasks.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
Alfred Gedeon 587a83d647 Style: uncrustify kernel files 5 years ago
Alfred Gedeon 2c530ba5c3 Style: uncrustify 5 years ago
Alfred Gedeon 718178c68a Style: uncrusitfy 5 years ago
Alfred Gedeon a5dbc2b1de Style: uncrustify kernel files 5 years ago
Gaurav-Aggarwal-AWS c4b4156fcf
Fix out of offset errors when LTO is enabled (#71)
When Link Time Optimization (LTO) is enabled, some of the LDR
instructions result in out of range access. The reason is that the
default generated literal pool is too far and not within the permissible
range of 4K.

This commit adds LTORG assembly instructions at required places to
ensure that access to literals remain in the permissible range of 4K.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
RichardBarry bac101c988
Fix/clear MIE bit in initial RISC-V mstatus register. (#57)
* fix: CLEAR MIE BIT IN INITIAL RISC-V MSTATUS VALUE
The MIE bit in the RISC-V MSTATUS register is used to globally enable
or disable interrupts.  It is copied into the MPIE bit and cleared
on entry to an interrupt, and then copied back from the MPIE bit on
exit from an interrupt.

When a task is created it is given an initial MSTATUS value that is
derived from the current MSTATUS value with the MPIE bit force to 1,
but the MIE bit is not forced into any state.  This change forces
the MIE bit to 0 (interrupts disabled).

Why:
If a task is created before the scheduler is started the MIE bit
will happen to be 0 (interrupts disabled), which is fine.  If a
task is created after the scheduler has been started the MIE bit
is set (interrupts enabled), causing interrupts to unintentionally
become enabled inside the interrupt in which the task is first
moved to the running state - effectively breaking a critical
section which in turn could cause a crash if enabling interrupts
causes interrupts to nest.  It is only an issue when starting a
newly created task that was created after the scheduler was started.

Related Issues:
https://forums.freertos.org/t/risc-v-port-pxportinitialisestack-issue-about-mstatus-value-onto-the-stack/9622
Co-authored-by: Cobus van Eeden <35851496+cobusve@users.noreply.github.com>
5 years ago
Yuhui Zheng 6e7523041d
GCC/ATmegaxxxx port path and name change. (#51)
Moving ATmega port to third party directory, and mature it there. Once we are fully done, the port could then be moved back to portable/GCC.
5 years ago
Phillip Stevens 1abca83c89
ATmegaxxxx - generalised support (#48)
ATmegaxxxx - generalised support. Please see README.md included in the same PR for usage and limitations.
5 years ago
Gaurav-Aggarwal-AWS 07e672c448
Add definition of portDONT_DISCARD to ARMv7-M ports (#50)
Enabling Link Time Optimization (LTO) causes some of the functions used
in assembly to be incorrectly stripped off, resulting in linker error.
To avoid this, these functions are marked with portDONT_DISCARD macro,
definition of which is port specific. This commit adds the definition
of portDONT_DISCARD for ARMv7-M ports.

Signed-off-by: Gaurav Aggarwal
5 years ago
Gaurav-Aggarwal-AWS 334de5d8ab
Enable ARMv7-M MPU ports to place FreeRTOS kernel code outside of flash (#46)
Problem Description
-------------------
The current flash organization in ARMv7-M MPU ports looks as follows:

__FLASH_segment_start__ ------->+-----------+<----- __FLASH_segment_start__
                                |  Vector   |
                                |   Table   |
                                |     +     |
                                |   Kernel  |
                                |    Code   |
                                +-----------+<-----  __privileged_functions_end__
                                |           |
                                |           |
                                |           |
                                |   Other   |
                                |   Code    |
                                |           |
                                |           |
                                |           |
   __FLASH_segment_end__ ------>+-----------+

The FreeRTOS kernel sets up the following MPU regions:

* Unprivileged Code - __FLASH_segment_start__ to __FLASH_segment_end__.
* Privileged Code - __FLASH_segment_start__ to __privileged_functions_end__.

The above setup assumes that the FreeRTOS kernel code
(i.e. privileged_functions) is placed at the beginning of the flash and,
therefore, uses __FLASH_segment_start__ as the starting location of the
privileged code. This prevents a user from placing the FreeRTOS kernel
code outside of flash (say to an external RAM) and still have vector
table at the beginning of flash (which is many times a hardware
requirement).

Solution
--------
This commit addresses the above limitation by using a new variable
__privileged_functions_start__ as the starting location of the
privileged code. This enables users to place the FreeRTOS kernel code
wherever they choose.

The FreeRTOS kernel now sets up the following MPU regions:

* Unprivileged Code - __FLASH_segment_start__ to __FLASH_segment_end__.
* Privileged Code - __privileged_functions_start__ to __privileged_functions_end__.

As a result, a user can now place the kernel code to an external RAM. A
possible organization is:

                                 Flash              External RAM
                              +------------+        +-----------+<------ __privileged_functions_start__
                              |   Vector   |        |           |
                              |   Table    |        |           |
                              |            |        |           |
__FLASH_segment_start__ ----->+------------+        |   Kernel  |
                              |            |        |    Code   |
                              |            |        |           |
                              |            |        |           |
                              |            |        |           |
                              |   Other    |        |           |
                              |    Code    |        +-----------+<------ __privileged_functions_end__
                              |            |
                              |            |
                              |            |
  __FLASH_segment_end__ ----->+------------+

Note that the above configuration places the vector table in an unmapped
region. This is okay because we enable the background region, and so the
vector table will still be accessible to the privileged code and not
accessible to the unprivileged code (vector table is only needed by the
privileged code).

Backward Compatibility
----------------------
The FreeRTOS kernel code now uses a new variable, namely
__privileged_functions_start__, which needs to be exported from linker
script to indicate the starting location of the privileged code. All of
our existing demos already export this variable and therefore, they will
continue to work.

If a user has created a project which does not export this variable,
they will get a linker error for unresolved symbol
__privileged_functions_start__. They need to export a variable
__privileged_functions_start__ with the value equal to
__FLASH_segment_start__.

Issue
-----
https://sourceforge.net/p/freertos/feature-requests/56/

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
Gaurav-Aggarwal-AWS 177e79fc79
Add "Tickless Idle" support for ARMv8M ports (#29)
Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
5 years ago
Vladimir Umek 9b02ee0af2 Cortex-A9 port: Adding stack alignment directive to assembly code 5 years ago
Yuhui.Zheng 88e32327e9
version bump to v10.3.1 (#16)
* Verion bump from 10.3.0 to 10.3.1.
* version bump in task.h
* change history for 10.3.1.
5 years ago
Yuhui Zheng 210b1ffcc8 Re-sync with upstream and stripping away none kernel related. 5 years ago