Merge pull request #614 from FrankBoesing/patch-1

Reduce memory usage (wasted RAM)
PaulStoffregen · Sep 26, 2021 · 2e2dcf7 · 2e2dcf7
2 parents 6d0e3ae + 918343c
commit 2e2dcf7
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Showing 5 changed files with 21 additions and 15 deletions.
diff --git a/teensy4/imxrt1062.ld b/teensy4/imxrt1062.ld
@@ -52,13 +52,15 @@ SECTIONS
 	} > ITCM  AT> FLASH
 
 	.data : {
-		*(.rodata*)
-		*(.data*)
+    		*(.endpoint_queue)    
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*)))
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.data*)))
+   		 KEEP(*(.vectorsram))
 	} > DTCM  AT> FLASH
 
 	.bss ALIGN(4) : {
-		*(.bss*)
-		*(COMMON)
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.bss*)))
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(COMMON)))
 		. = ALIGN(32);
 		. = . + 32; /* MPU to trap stack overflow */
 	} > DTCM

diff --git a/teensy4/imxrt1062_mm.ld b/teensy4/imxrt1062_mm.ld
@@ -52,13 +52,15 @@ SECTIONS
 	} > ITCM  AT> FLASH
 
 	.data : {
-		*(.rodata*)
-		*(.data*)
+    		*(.endpoint_queue)    
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*)))
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.data*)))
+    		KEEP(*(.vectorsram))	
 	} > DTCM  AT> FLASH
 
 	.bss ALIGN(4) : {
-		*(.bss*)
-		*(COMMON)
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.bss*)))
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(COMMON)))
 		. = ALIGN(32);
 		. = . + 32; /* MPU to trap stack overflow */
 	} > DTCM

diff --git a/teensy4/imxrt1062_t41.ld b/teensy4/imxrt1062_t41.ld
@@ -53,13 +53,15 @@ SECTIONS
 	} > ITCM  AT> FLASH
 
 	.data : {
-		*(.rodata*)
-		*(.data*)
+		*(.endpoint_queue)   
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*)))
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.data*)))
+		KEEP(*(.vectorsram))
 	} > DTCM  AT> FLASH
 
 	.bss ALIGN(4) : {
-		*(.bss*)
-		*(COMMON)
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.bss*)))
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(COMMON)))
 		. = ALIGN(32);
 		. = . + 32; /* MPU to trap stack overflow */
 	} > DTCM
@@ -71,7 +73,7 @@ SECTIONS
 	} > RAM
 
 	.bss.extram (NOLOAD) : {
-		*(.externalram)
+		*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.externalram)))
 		. = ALIGN(32);
 	} > ERAM
 

diff --git a/teensy4/startup.c b/teensy4/startup.c
@@ -21,7 +21,7 @@ extern unsigned long _estack;
 extern unsigned long _extram_start;
 extern unsigned long _extram_end;
 
-__attribute__ ((used, aligned(1024)))
+__attribute__ ((used, aligned(1024), section(".vectorsram")))
 void (* volatile _VectorsRam[NVIC_NUM_INTERRUPTS+16])(void);
 
 static void memory_copy(uint32_t *dest, const uint32_t *src, uint32_t *dest_end);

diff --git a/teensy4/usb.c b/teensy4/usb.c
@@ -62,7 +62,7 @@ struct endpoint_struct {
 uint8_t experimental_buffer[1152] __attribute__ ((section(".dmabuffers"), aligned(64)));
 #endif
 
-endpoint_t endpoint_queue_head[(NUM_ENDPOINTS+1)*2] __attribute__ ((used, aligned(4096)));
+endpoint_t endpoint_queue_head[(NUM_ENDPOINTS+1)*2] __attribute__ ((used, aligned(4096), section(".endpoint_queue") ));
 
 transfer_t endpoint0_transfer_data __attribute__ ((used, aligned(32)));
 transfer_t endpoint0_transfer_ack  __attribute__ ((used, aligned(32)));