platforms: rp: link ram functions to ramtext section

With the 2.0.0 pico-sdk release it is possible to re-define the custom
pico-sdk linker sections, allowing us to drop the custom linker script
which introduced the `.time_critical` section in ram. This section is
for functions we do not want to execute from flash e.g. everything that
must be fast or available if the XIP flash is deactivated e.g. when
programming the flash itself.

platforms/chibios/boards/common/ld/RP2040_FLASH_TIMECRIT.ld

@@ -1,117 +0,0 @@
-/*
-    ChibiOS - Copyright (C) 2006..2021 Giovanni Di Sirio
-
-    Licensed under the Apache License, Version 2.0 (the "License");
-    you may not use this file except in compliance with the License.
-    You may obtain a copy of the License at
-
-        http://www.apache.org/licenses/LICENSE-2.0
-
-    Unless required by applicable law or agreed to in writing, software
-    distributed under the License is distributed on an "AS IS" BASIS,
-    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-    See the License for the specific language governing permissions and
-    limitations under the License.
-*/
-
-/*
- * RP2040 memory setup.
- */
-MEMORY
-{
-    flash0 (rx) : org = 0x00000000, len = 16k   /* ROM                  */
-    flash1 (rx) : org = 0x10000000, len = DEFINED(FLASH_LEN) ? FLASH_LEN : 2048k /* XIP */
-    flash2 (rx) : org = 0x00000000, len = 0
-    flash3 (rx) : org = 0x00000000, len = 0
-    flash4 (rx) : org = 0x00000000, len = 0
-    flash5 (rx) : org = 0x00000000, len = 0
-    flash6 (rx) : org = 0x00000000, len = 0
-    flash7 (rx) : org = 0x00000000, len = 0
-    ram0   (wx) : org = 0x20000000, len = 256k  /* SRAM0 striped        */
-    ram1   (wx) : org = 0x00000000, len = 256k  /* SRAM0 non striped    */
-    ram2   (wx) : org = 0x00000000, len = 0
-    ram3   (wx) : org = 0x00000000, len = 0
-    ram4   (wx) : org = 0x20040000, len = 4k    /* SRAM4                */
-    ram5   (wx) : org = 0x20041000, len = 4k    /* SRAM5                */
-    ram6   (wx) : org = 0x00000000, len = 0
-    ram7   (wx) : org = 0x20041f00, len = 256   /* SRAM5 boot           */
-}
-
-/* For each data/text section two region are defined, a virtual region
-   and a load region (_LMA suffix).*/
-
-/* Flash region to be used for exception vectors.*/
-REGION_ALIAS("VECTORS_FLASH", flash1);
-REGION_ALIAS("VECTORS_FLASH_LMA", flash1);
-
-/* Flash region to be used for constructors and destructors.*/
-REGION_ALIAS("XTORS_FLASH", flash1);
-REGION_ALIAS("XTORS_FLASH_LMA", flash1);
-
-/* Flash region to be used for code text.*/
-REGION_ALIAS("TEXT_FLASH", flash1);
-REGION_ALIAS("TEXT_FLASH_LMA", flash1);
-
-/* Flash region to be used for read only data.*/
-REGION_ALIAS("RODATA_FLASH", flash1);
-REGION_ALIAS("RODATA_FLASH_LMA", flash1);
-
-/* Flash region to be used for various.*/
-REGION_ALIAS("VARIOUS_FLASH", flash1);
-REGION_ALIAS("VARIOUS_FLASH_LMA", flash1);
-
-/* Flash region to be used for RAM(n) initialization data.*/
-REGION_ALIAS("RAM_INIT_FLASH_LMA", flash1);
-
-/* RAM region to be used for Main stack. This stack accommodates the processing
-   of all exceptions and interrupts.*/
-REGION_ALIAS("MAIN_STACK_RAM", ram4);
-
-/* RAM region to be used for the process stack. This is the stack used by
-   the main() function.*/
-REGION_ALIAS("PROCESS_STACK_RAM", ram4);
-
-/* RAM region to be used for Main stack. This stack accommodates the processing
-   of all exceptions and interrupts.*/
-REGION_ALIAS("C1_MAIN_STACK_RAM", ram5);
-
-/* RAM region to be used for the process stack. This is the stack used by
-   the main() function.*/
-REGION_ALIAS("C1_PROCESS_STACK_RAM", ram5);
-
-/* RAM region to be used for data segment.*/
-REGION_ALIAS("DATA_RAM", ram0);
-REGION_ALIAS("DATA_RAM_LMA", flash1);
-
-/* RAM region to be used for BSS segment.*/
-REGION_ALIAS("BSS_RAM", ram0);
-
-/* RAM region to be used for the default heap.*/
-REGION_ALIAS("HEAP_RAM", ram0);
-
-SECTIONS
-{
-   .flash_begin : {
-      __flash_binary_start = .;
-   } > flash1
-
-   .boot2 : {
-      __boot2_start__ = .;
-      KEEP (*(.boot2))
-      __boot2_end__ = .;
-   } > flash1
-}
-
-/* Generic rules inclusion.*/
-INCLUDE rules_stacks.ld
-INCLUDE rules_stacks_c1.ld
-INCLUDE RP2040_rules_code_with_boot2.ld
-INCLUDE RP2040_rules_data_with_timecrit.ld
-INCLUDE rules_memory.ld
-
-SECTIONS
-{
-   .flash_end : {
-      __flash_binary_end = .;
-   } > flash1
-}

platforms/chibios/boards/common/ld/RP2040_rules_data_with_timecrit.ld

@@ -1,46 +0,0 @@
-/*
-    ChibiOS - Copyright (C) 2006..2018 Giovanni Di Sirio
-
-    Licensed under the Apache License, Version 2.0 (the "License");
-    you may not use this file except in compliance with the License.
-    You may obtain a copy of the License at
-
-        http://www.apache.org/licenses/LICENSE-2.0
-
-    Unless required by applicable law or agreed to in writing, software
-    distributed under the License is distributed on an "AS IS" BASIS,
-    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-    See the License for the specific language governing permissions and
-    limitations under the License.
-*/
-
-SECTIONS
-{
-    .data : ALIGN(4)
-    {
-        PROVIDE(_textdata = LOADADDR(.data));
-        PROVIDE(_data = .);
-        __textdata_base__ = LOADADDR(.data);
-        __data_base__ = .;
-        *(vtable)
-        *(.time_critical*)
-        . = ALIGN(4);
-        *(.data)
-        *(.data.*)
-        *(.ramtext)
-        . = ALIGN(4);
-        PROVIDE(_edata = .);
-        __data_end__ = .;
-    } > DATA_RAM AT > DATA_RAM_LMA
-
-    .bss (NOLOAD) : ALIGN(4)
-    {
-        __bss_base__ = .;
-        *(.bss)
-        *(.bss.*)
-        *(COMMON)
-        . = ALIGN(4);
-        __bss_end__ = .;
-        PROVIDE(end = .);
-    } > BSS_RAM
-}

platforms/chibios/mcu_selection.mk

@@ -159,8 +159,8 @@ ifneq ($(findstring RP2040, $(MCU)),)
   # Linker script to use
   # - it should exist either in <chibios>/os/common/ports/ARMCMx/compilers/GCC/ld/
   #   or <keyboard_dir>/ld/
+  MCU_LDSCRIPT ?= RP2040_FLASH
   STARTUPLD_CONTRIB = $(CHIBIOS_CONTRIB)/os/common/startup/ARMCMx/compilers/GCC/ld
-  MCU_LDSCRIPT ?= RP2040_FLASH_TIMECRIT
   LDFLAGS += -L $(STARTUPLD_CONTRIB)
 
   # Startup code to use

platforms/chibios/vendors/RP/pico_sdk_shims.h

@@ -0,0 +1,12 @@
+// Copyright 2024 Stefan Kerkmann
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#ifndef __ASSEMBLER__
+
+#define __not_in_flash(group) __attribute__((section(".ramtext." group)))
+
+#else 
+
+#define RAM_SECTION_NAME(x) .ramtext.##x
+
+#endif

platforms/chibios/vendors/RP/rp_common.mk

@@ -12,9 +12,11 @@ endif
 ##############################################################################
 ADEFS  += -DCRT0_VTOR_INIT=1 \
 		  -DCRT0_EXTRA_CORES_NUMBER=0 \
-          -DCRT0_INIT_VECTORS=1
+          -DCRT0_INIT_VECTORS=1 \
+          -DPICO_CONFIG_RTOS_ADAPTER_HEADER=$(PLATFORM_RP_PATH)/pico_sdk_shims.h
 
-CFLAGS += -DNDEBUG
+CFLAGS += -DNDEBUG \
+          -DPICO_CONFIG_RTOS_ADAPTER_HEADER=$(PLATFORM_RP_PATH)/pico_sdk_shims.h
 
 #
 # Pico SDK source and header files needed by QMK and ChibiOS