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aethanielaethaniel
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[bl] Fixing the jump to sketch
1 parent f352830 commit 4667b66

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5 files changed

+50
-49
lines changed

5 files changed

+50
-49
lines changed

‎bootloaders/zero/Makefile‎

Lines changed: 5 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -65,9 +65,9 @@ SIZE=$(ARM_GCC_PATH)size
6565
#-w
6666
CFLAGS=-mthumb -mcpu=cortex-m0plus -Wall -c -std=gnu99 -ffunction-sections -fdata-sections -nostdlib -nostartfiles --param max-inline-insns-single=500
6767
ifdef DEBUG
68-
CFLAGS+=-g3 -O1
68+
CFLAGS+=-g3 -O1 -DDEBUG=1
6969
else
70-
CFLAGS+=-Os
70+
CFLAGS+=-Os -DDEBUG=0
7171
endif
7272
#CFLAGS_EXTRA?=-D__SAMD21G18A__ -DUSB_PID_LOW=0x4D -DUSB_PID_HIGH=0x00
7373
CFLAGS_EXTRA?=-D__SAMD21J18A__ -DUSB_PID_LOW=0x01 -DUSB_PID_HIGH=0xE0
@@ -153,8 +153,9 @@ copy_for_atmel_studio: $(EXECUTABLE)
153153

154154
clean_for_atmel_studio:
155155
@echo ----------------------------------------------------------
156-
@echo Atmel Studio detected, cleaing ELF from project root
157-
-$(RM) $(BUILD_PATH)/$(ELF) .
156+
@echo Atmel Studio detected, cleaning ELF from project root
157+
# -$(RM) $(BUILD_PATH)/$(ELF)
158+
-$(RM) ./$(ELF)
158159

159160
clean: $(AS_CLEAN)
160161
@echo ----------------------------------------------------------

‎bootloaders/zero/bootloader_samd21x18.ld‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -58,7 +58,7 @@ MEMORY
5858
* __StackLimit
5959
* __StackTop
6060
* __stack
61-
* __app_start_address
61+
* __sketch_stackptr
6262
*/
6363
ENTRY(Reset_Handler)
6464

@@ -144,7 +144,7 @@ SECTIONS
144144
*/
145145

146146
__etext = .;
147-
PROVIDE(__app_start_address = ORIGIN(FLASH) + LENGTH(FLASH));
147+
PROVIDE(__sketch_stackptr = ORIGIN(FLASH) + LENGTH(FLASH));
148148

149149

150150
.data : AT (__etext)

‎bootloaders/zero/main.c‎

Lines changed: 42 additions & 18 deletions
Original file line numberDiff line numberDiff line change
@@ -70,10 +70,12 @@
7070
#include "sam_ba_usb.h"
7171
#include "sam_ba_cdc.h"
7272

73-
extern uint32_t __app_start_address;
73+
extern uint32_t __sketch_stackptr; // Exported value from linker script
7474
extern void board_init(void);
7575

76-
//static void check_start_application(void);
76+
#if (defined DEBUG) && (DEBUG == 1)
77+
volatile uint32_t* pulSketch_Start_Address;
78+
#endif
7779

7880
static volatile bool main_b_cdc_enable = false;
7981

@@ -105,7 +107,9 @@ static void check_start_application(void)
105107
/* First tap */
106108
BOOT_DOUBLE_TAP_DATA = DOUBLE_TAP_MAGIC;
107109

108-
/* Wait 0.5sec to see if the user tap reset again */
110+
/* Wait 0.5sec to see if the user tap reset again.
111+
* The loop value is based on SAMD21 default 1MHz clock @ reset.
112+
*/
109113
for (uint32_t i=0; i<125000; i++) /* 500ms */
110114
/* force compiler to not optimize this... */
111115
__asm__ __volatile__("");
@@ -115,51 +119,71 @@ static void check_start_application(void)
115119
}
116120
#endif
117121

118-
uint32_t app_start_address;
122+
#if (!defined DEBUG) || ((defined DEBUG) && (DEBUG == 0))
123+
uint32_t* pulSketch_Start_Address;
124+
#endif
119125

120-
/* Load the Reset Handler address of the application */
121-
app_start_address = *(uint32_t *)(&__app_start_address + 4);
126+
/*
127+
* Test sketch stack pointer @ &__sketch_stackptr
128+
* Stay in SAM-BA if value @ (&__sketch_stackptr) == 0xFFFFFFFF (Erased flash cell value)
129+
*/
130+
if (__sketch_stackptr == 0xFFFFFFFF)
131+
{
132+
/* Stay in bootloader */
133+
return;
134+
}
135+
136+
/*
137+
* Load the sketch Reset Handler address
138+
* __sketch_stackptr is exported from linker script and point on first 32b word of sketch vector table
139+
* First 32b word is sketch stack
140+
* Second 32b word is sketch entry point: Reset_Handler()
141+
*/
142+
pulSketch_Start_Address = &__sketch_stackptr ;
143+
pulSketch_Start_Address++ ;
122144

123-
/**
124-
* Test reset vector of application @__app_start_address+4
125-
* Stay in SAM-BA if *(__app_start_address+0x4) == 0xFFFFFFFF
126-
* Application erased condition
145+
/*
146+
* Test reset vector of sketch @ &__sketch_stackptr+4
147+
* Stay in SAM-BA if this function is not aligned enough, ie not valid
148+
* The value 0x01 is the 'Thumb mode' bit added by linker.
127149
*/
128-
if (app_start_address == 0xFFFFFFFF)
150+
if ( (*pulSketch_Start_Address & ~SCB_VTOR_TBLOFF_Msk) != 0x01 )
129151
{
130152
/* Stay in bootloader */
131153
return;
132154
}
133155

156+
/*
134157
#if defined(BOOT_LOAD_PIN)
135158
volatile PortGroup *boot_port = (volatile PortGroup *)(&(PORT->Group[BOOT_LOAD_PIN / 32]));
136159
volatile bool boot_en;
137160
138-
/* Enable the input mode in Boot GPIO Pin */
161+
// Enable the input mode in Boot GPIO Pin
139162
boot_port->DIRCLR.reg = BOOT_PIN_MASK;
140163
boot_port->PINCFG[BOOT_LOAD_PIN & 0x1F].reg = PORT_PINCFG_INEN | PORT_PINCFG_PULLEN;
141164
boot_port->OUTSET.reg = BOOT_PIN_MASK;
142-
/* Read the BOOT_LOAD_PIN status */
165+
// Read the BOOT_LOAD_PIN status
143166
boot_en = (boot_port->IN.reg) & BOOT_PIN_MASK;
144167
145-
/* Check the bootloader enable condition */
168+
// Check the bootloader enable condition
146169
if (!boot_en)
147170
{
148-
/* Stay in bootloader */
171+
// Stay in bootloader
149172
return;
150173
}
151174
#endif
175+
*/
152176

153177
LED_on();
154178

155179
/* Rebase the Stack Pointer */
156-
__set_MSP(*(uint32_t *) &__app_start_address);
180+
__set_MSP( (uint32_t)(*(pulSketch_Start_Address-1)) );
157181

158182
/* Rebase the vector table base address */
159-
SCB->VTOR = ((uint32_t) &__app_start_address & SCB_VTOR_TBLOFF_Msk);
183+
SCB->VTOR = ((uint32_t)(pulSketch_Start_Address-1) & SCB_VTOR_TBLOFF_Msk);
160184

161185
/* Jump to application Reset Handler in the application */
162-
asm("bx %0"::"r"(app_start_address));
186+
asm("bx %0"::"r"(*pulSketch_Start_Address));
163187
}
164188

165189
#if DEBUG_ENABLE

‎bootloaders/zero/samd21_sam_ba.bin‎

8 Bytes
Binary file not shown.

‎bootloaders/zero/samd21_sam_ba.cproj‎

Lines changed: 1 addition & 25 deletions
Original file line numberDiff line numberDiff line change
@@ -69,10 +69,6 @@
6969
<Value>NDEBUG</Value>
7070
</ListValues>
7171
</armgcc.compiler.symbols.DefSymbols>
72-
<armgcc.compiler.directories.IncludePaths>
73-
<ListValues>
74-
</ListValues>
75-
</armgcc.compiler.directories.IncludePaths>
7672
<armgcc.compiler.optimization.level>Optimize for size (-Os)</armgcc.compiler.optimization.level>
7773
<armgcc.compiler.optimization.PrepareFunctionsForGarbageCollection>True</armgcc.compiler.optimization.PrepareFunctionsForGarbageCollection>
7874
<armgcc.compiler.warnings.AllWarnings>True</armgcc.compiler.warnings.AllWarnings>
@@ -81,16 +77,8 @@
8177
<Value>libm</Value>
8278
</ListValues>
8379
</armgcc.linker.libraries.Libraries>
84-
<armgcc.linker.libraries.LibrarySearchPaths>
85-
<ListValues>
86-
</ListValues>
87-
</armgcc.linker.libraries.LibrarySearchPaths>
8880
<armgcc.linker.optimization.GarbageCollectUnusedSections>True</armgcc.linker.optimization.GarbageCollectUnusedSections>
8981
<armgcc.linker.miscellaneous.LinkerFlags>-Tsamd21j18a_flash.ld</armgcc.linker.miscellaneous.LinkerFlags>
90-
<armgcc.preprocessingassembler.general.IncludePaths>
91-
<ListValues>
92-
</ListValues>
93-
</armgcc.preprocessingassembler.general.IncludePaths>
9482
</ArmGcc>
9583
</ToolchainSettings>
9684
</PropertyGroup>
@@ -107,10 +95,6 @@
10795
<Value>DEBUG</Value>
10896
</ListValues>
10997
</armgcc.compiler.symbols.DefSymbols>
110-
<armgcc.compiler.directories.IncludePaths>
111-
<ListValues>
112-
</ListValues>
113-
</armgcc.compiler.directories.IncludePaths>
11498
<armgcc.compiler.optimization.level>Optimize (-O1)</armgcc.compiler.optimization.level>
11599
<armgcc.compiler.optimization.PrepareFunctionsForGarbageCollection>True</armgcc.compiler.optimization.PrepareFunctionsForGarbageCollection>
116100
<armgcc.compiler.optimization.DebugLevel>Maximum (-g3)</armgcc.compiler.optimization.DebugLevel>
@@ -120,17 +104,9 @@
120104
<Value>libm</Value>
121105
</ListValues>
122106
</armgcc.linker.libraries.Libraries>
123-
<armgcc.linker.libraries.LibrarySearchPaths>
124-
<ListValues>
125-
</ListValues>
126-
</armgcc.linker.libraries.LibrarySearchPaths>
127107
<armgcc.linker.optimization.GarbageCollectUnusedSections>True</armgcc.linker.optimization.GarbageCollectUnusedSections>
128108
<armgcc.linker.miscellaneous.LinkerFlags>-Tsamd21j18a_flash.ld</armgcc.linker.miscellaneous.LinkerFlags>
129109
<armgcc.assembler.debugging.DebugLevel>Default (-g)</armgcc.assembler.debugging.DebugLevel>
130-
<armgcc.preprocessingassembler.general.IncludePaths>
131-
<ListValues>
132-
</ListValues>
133-
</armgcc.preprocessingassembler.general.IncludePaths>
134110
<armgcc.preprocessingassembler.debugging.DebugLevel>Default (-Wa,-g)</armgcc.preprocessingassembler.debugging.DebugLevel>
135111
</ArmGcc>
136112
</ToolchainSettings>
@@ -241,4 +217,4 @@
241217
</None>
242218
</ItemGroup>
243219
<Import Project="$(AVRSTUDIO_EXE_PATH)\\Vs\\Compiler.targets" />
244-
</Project>
220+
</Project>

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