Add minimal STM32F103C6 support (#17853)

Unfortunately, the crippled versions of “Bluepill” boards with
STM32F103C6xx chips instead of STM32F103C8xx are now sold all over the
place, sometimes advertised in a confusing way to make the difference
not noticeable until too late.  Add minimal support for these MCUs in
the common “Bluepill with stm32duino” configuration, so that it could be
possible to make something useful from those boards (although fitting
QMK into the available 24 KiB of flash may be rather hard).

(In fact, I'm not sure whether the “STM32” part of the chip name is
actually correct for those boards of uncertain origin, so the onekey
board name is `bluepill_f103c6`; another reason for that name is to
match the existing `blackpill_f401` and `blackpill_f411`.)

The EEPROM emulation support is not included on purpose, because
enabling it without having a working firmware size check would be
irresponsible with such flash size (the chance that someone would build
a firmware where the EEPROM backing store ends up overlapping some
firmware code is really high).  Other than that, enabling the EEPROM
emulation code is mostly trivial (the `wear_leveling` driver with the
`embedded_flash` backing store even works without any custom
configuration, although its code is significantly larger than the
`vendor` driver, which may also be important for such flash size).

5 files changed, 28 insertions, 1 deletions

diff --git a/platforms/chibios/boards/STM32_F103_STM32DUINO/board/board.c b/platforms/chibios/boards/STM32_F103_STM32DUINO/board/board.c
index cba977da77..e82e1d37ce 100644
--- a/platforms/chibios/boards/STM32_F103_STM32DUINO/board/board.c
+++ b/platforms/chibios/boards/STM32_F103_STM32DUINO/board/board.c
@@ -28,7 +28,9 @@ const PALConfig pal_default_config =
   {VAL_GPIOBODR, VAL_GPIOBCRL, VAL_GPIOBCRH},
   {VAL_GPIOCODR, VAL_GPIOCCRL, VAL_GPIOCCRH},
   {VAL_GPIODODR, VAL_GPIODCRL, VAL_GPIODCRH},
+#    if STM32_HAS_GPIOE
   {VAL_GPIOEODR, VAL_GPIOECRL, VAL_GPIOECRH},
+#    endif
 };
 #endif
 
diff --git a/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103x6_stm32duino_bootloader.ld b/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103x6_stm32duino_bootloader.ld
new file mode 100644
index 0000000000..18aaff2a23
--- /dev/null
+++ b/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103x6_stm32duino_bootloader.ld
@@ -0,0 +1,23 @@
+/*
+    ChibiOS - Copyright (C) 2006..2016 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.
+*/
+
+/*
+ * STM32F103x6 memory setup for use with the STM32Duino bootloader.
+ */
+f103_flash_size = 32k;
+f103_ram_size = 10k;
+
+INCLUDE stm32duino_bootloader_common.ld
diff --git a/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103x8_stm32duino_bootloader.ld b/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103x8_stm32duino_bootloader.ld
index a4bd566b59..465af12cab 100644
--- a/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103x8_stm32duino_bootloader.ld
+++ b/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103x8_stm32duino_bootloader.ld
@@ -18,5 +18,6 @@
  * STM32F103x8 memory setup for use with the STM32Duino bootloader.
  */
 f103_flash_size = 64k;
+f103_ram_size = 20k;
 
 INCLUDE stm32duino_bootloader_common.ld
diff --git a/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103xB_stm32duino_bootloader.ld b/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103xB_stm32duino_bootloader.ld
index dc47400dc5..3a47a33156 100644
--- a/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103xB_stm32duino_bootloader.ld
+++ b/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/STM32F103xB_stm32duino_bootloader.ld
@@ -18,5 +18,6 @@
  * STM32F103xB memory setup for use with the STM32Duino bootloader.
  */
 f103_flash_size = 128k;
+f103_ram_size = 20k;
 
 INCLUDE stm32duino_bootloader_common.ld
diff --git a/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/stm32duino_bootloader_common.ld b/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/stm32duino_bootloader_common.ld
index 76cd3153be..1466ae7ed2 100644
--- a/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/stm32duino_bootloader_common.ld
+++ b/platforms/chibios/boards/STM32_F103_STM32DUINO/ld/stm32duino_bootloader_common.ld
@@ -27,7 +27,7 @@ MEMORY
     flash5  : org = 0x00000000, len = 0
     flash6  : org = 0x00000000, len = 0
     flash7  : org = 0x00000000, len = 0
-    ram0    : org = 0x20000000, len = 20k
+    ram0    : org = 0x20000000, len = f103_ram_size
     ram1    : org = 0x00000000, len = 0
     ram2    : org = 0x00000000, len = 0
     ram3    : org = 0x00000000, len = 0