WIP: Icesugar support

FemtoRV/BOARDS/icesugar.mk

@@ -1,19 +1,18 @@
-YOSYS_ICESUGAR_OPT=-DICE_SUGAR -q -p "synth_ice40 -relut -top $(PROJECTNAME) -json $(PROJECTNAME).json"
+YOSYS_ICESUGAR_OPT=-DICE_SUGAR -q -p "synth_ice40 -abc9 -device u -dsp -top $(PROJECTNAME) -json $(PROJECTNAME).json"
 NEXTPNR_ICESUGAR_OPT=--force --json $(PROJECTNAME).json --pcf BOARDS/icesugar.pcf --asc $(PROJECTNAME).asc \
-                       --freq 12 --up5k --package sg48
+                       --freq 12 --up5k --package sg48 --opt-timing
 
 #######################################################################################################################
 
 ICESUGAR: ICESUGAR.firmware_config ICESUGAR.synth ICESUGAR.prog
 
-ICESUGAR.synth: FIRMWARE/firmware.hex 
-	TOOLS/make_config.sh -DICE_SUGAR
+ICESUGAR.synth:
 	yosys $(YOSYS_ICESUGAR_OPT) $(VERILOGS)
 	nextpnr-ice40 $(NEXTPNR_ICESUGAR_OPT)
 	icetime -p BOARDS/icesugar.pcf -P sg48 -r $(PROJECTNAME).timings -d up5k -t $(PROJECTNAME).asc
 	icepack -s $(PROJECTNAME).asc $(PROJECTNAME).bin
 
-ICESUGAR.show: FIRMWARE/firmware.hex 
+ICESUGAR.show:
 	yosys $(YOSYS_ICESUGAR_OPT) $(VERILOGS)
 	nextpnr-ice40 $(NEXTPNR_ICESUGAR_OPT) --gui
 
@@ -22,4 +21,4 @@ ICESUGAR.prog:
 
 ICESUGAR.firmware_config:
 	BOARD=icesugar TOOLS/make_config.sh -DICE_SUGAR
-	(cd FIRMWARE; make libs)
+	(cd FIRMWARE; make libs)

FemtoRV/BOARDS/icesugar.pcf

@@ -3,27 +3,17 @@ set_io pclk 35
 set_io TXD 6
 set_io RXD 4
 
+# https://github.com/wuxx/icesugar/blob/master/src/basic/verilog/flash/top.v 
+# from ice40 ultraplus datasheet, miso/mosi are inverted in flash-prog mode
 set_io spi_cs_n 16
-set_io spi_miso 14
-set_io spi_mosi 17
+set_io spi_miso 17
+set_io spi_mosi 14
 set_io spi_clk  15
 
-set_io oled_DIN  46
-set_io oled_CLK  44
-set_io oled_CS   42
-set_io oled_DC   37
-set_io oled_RST  36
-
-set_io D1 38
+set_io D1 45
 set_io D2 43
-set_io D3 45
-set_io D4 34
-set_io D5 31
-
-
-set_io ledmtx_DIN  27
-set_io ledmtx_CS   25
-set_io ledmtx_CLK  23
-
+set_io D3 38
+set_io D4 36
+set_io D5 37
 
-set_io RESET    18
+set_io RESET 9

FemtoRV/FIRMWARE/CRT/spiflash_icesugar.ld

@@ -0,0 +1,100 @@
+/* Linker script for programs stored in SPI flash */
+/* Inspired from picorv32/picosoc/sections.lds    */
+/*                                                */
+/* text sections are sent to BRAM                 */
+/* rodata sections are sent to flash              */
+/* bss sections are sent to BRAM                  */
+/* data sections are sent to BRAM and have        */
+/*  initialization data in flash.                 */
+/* AT keyword specifies LMA (Load Memory Address) */
+/*                                                */
+/* If you got a lot of code that does not fit in  */
+/* RAM, you may keep text sections in flash using */
+/*   spiflash_icebreaker_run_from_flash.ld        */
+
+
+MEMORY {
+    FLASH (rx)  : ORIGIN = 0x00820000, LENGTH = 0x100000    /* 4 MB in flash */
+    RAM   (rwx) : ORIGIN = 0x00000000, LENGTH = 0x20000     /* 128 kB in RAM */
+}
+
+SECTIONS {
+
+    /*
+     * I do not understand why, but if I do not put this section, I got
+     * an overlapping sections error with some programs (for instance pi.c
+     * or C++ programs)
+     */
+    .misc : {
+        . = ALIGN(4);
+        *(.eh_frame)
+        *(.eh_frame_hdr)
+        *(.init_array)
+        *(.gcc_except_table*)	
+    } >FLASH
+
+    /* C runtime initialization code and readonly data goes to the FLASH */
+    .text : {
+        . = ALIGN(4);
+        crt0_spiflash.o(.text)  /* c runtime initialization (code) */
+        . = ALIGN(4);
+        *(.rodata)              /* .rodata sections (constants, strings, etc.) */
+        *(.rodata*)             /* .rodata* sections (constants, strings, etc.) */
+        *(.srodata)             /* .rodata sections (constants, strings, etc.) */
+        *(.srodata*)            /* .rodata* sections (constants, strings, etc.) */
+        _etext = .;             /* define a global symbol at end of code */
+        _sidata = _etext;       /* This is used by the startup in order to initialize the .data section */
+    } >FLASH
+
+
+    /* 
+     * This is the initialized data and fastcode section
+     * The program executes knowing that the data is in the RAM
+     * but the loader puts the initial values in the FLASH (inidata).
+     * It is one task of the startup (crt0_spiflash.S) to copy the initial values from FLASH to RAM. 
+     */
+    .data_and_fastcode : AT ( _sidata ) {
+        . = ALIGN(4);
+        _sdata = .;        /* create a global symbol at data start; used by startup code in order to initialise the .data section in RAM */
+        _ram_start = .;    /* create a global symbol at ram start (e.g., for garbage collector) */
+
+	/* functions with attribute((section(".fastcode"))) */	
+	/* (e.g., some functions in femtoGL)                */
+	*(.fastcode*)      
+
+        *(.text)                /* .text sections (code) */
+        *(.text*)               /* .text* sections (code) */
+        . = ALIGN(4);
+
+	/* Initialized data */
+        *(.data)                     
+        *(.data*)          
+        *(.sdata)          
+        *(.sdata*)
+
+        . = ALIGN(4);
+        _edata = .;        /* define a global symbol at data end; used by startup code in order to initialise the .data section in RAM */
+    } > RAM
+
+    /* Uninitialized data section */
+    .bss : {
+        . = ALIGN(4);
+        _sbss = .;         /* define a global symbol at bss start; used by startup code */
+        *(.bss)
+        *(.bss*)
+        *(.sbss)
+        *(.sbss*)
+        *(COMMON)
+        . = ALIGN(4);
+        _ebss = .;         /* define a global symbol at bss end; used by startup code */
+    } >RAM
+
+    /* this is to define the start of the heap, and make sure we have a minimum size */
+    .heap : {
+        . = ALIGN(4);
+        _heap_start = .;    /* define a global symbol at heap start */
+	_end = .;           /* as expected by syscalls.c            */
+    } >RAM
+
+
+}

FemtoRV/FIRMWARE/LIBFEMTORV32/femtorv32.h

@@ -10,7 +10,7 @@
  * (much faster) RAM (but use it wisely, you only got 7kB).
  * Other devices are sufficient RAM to load all the code.
  */
-#if defined(ICE_STICK) || defined(ICE_BREAKER)
+#if defined(ICE_STICK) || defined(ICE_BREAKER) || defined(ICE_SUGAR)
 #define RV32_FASTCODE __attribute((section(".fastcode")))
 #else
 #define RV32_FASTCODE

FemtoRV/FIRMWARE/makefile.inc

@@ -83,6 +83,12 @@ RVGCC_LIB= $(RVTOOLCHAIN_LIB_DIR)/libc.a \
 # My utility that converts elf executables into a format understood by Verilog
 FIRMWARE_WORDS=$(FIRMWARE_DIR)/TOOLS/firmware_words
 
+ifeq ($(BOARD),icesugar)
+	TOOLCHAIN_PROG_CMD=icesprog -o 131072
+else
+	TOOLCHAIN_PROG_CMD=iceprog -o 128k
+endif
+
 ################################################################################
 
 RVINCS=-I$(FIRMWARE_DIR)/LIBFEMTOGL -I$(FIRMWARE_DIR)/LIBFEMTORV32 -I$(FIRMWARE_DIR)/LIBFEMTOC
@@ -142,7 +148,7 @@ FEMTORV32_LIBS_SMALL=-L$(RVTOOLCHAIN_LIB_DIR)\
 
 # Sends the generated executable in flat binary form to SPI flash
 %.prog: %.spiflash.bin
-	iceprog -o 128k $<
+	TOOLCHAIN_PROG_CMD $<
 
 # Generate a disassembly (for inspection if need be)
 %.list: %.baremetal.elf

FemtoRV/RTL/CONFIGS/icesugar_config.v

@@ -0,0 +1,46 @@
+// Default femtosoc configuration file for Icesugar (derived from Icebreaker)
+
+`define NRV_NEGATIVE_RESET
+/************************* Devices **********************************************************************************/
+
+`define NRV_IO_LEDS      // Mapped IO, LEDs D1,D2,D3,D4 (D5 is used to display errors)
+`define NRV_IO_UART      // Mapped IO, virtual UART (USB)
+//`define NRV_IO_SSD1351   // Mapped IO, 128x128x64K OLed screen
+//`define NRV_IO_MAX7219   // Mapped IO, 8x8 led matrix
+`define NRV_MAPPED_SPI_FLASH // SPI flash mapped in address space. Can be used with MINIRV32 to run code from SPI flash.
+
+/************************* Processor configuration ******************************************************************/
+
+`define NRV_FEMTORV32_QUARK
+//`define NRV_FEMTORV32_ELECTRON      // RV32IM
+//`define NRV_FEMTORV32_INTERMISSUM   // RV32IM  + IRQ
+//`define NRV_FEMTORV32_GRACILIS      // RV32IMC + IRQ
+//`define NRV_FEMTORV32_PETITBATEAU     // RV32IMFC + IRQ, does not fit on IceBreaker
+
+`define NRV_FREQ 12                 // Frequency in MHz. Recomm: 15 MHz   Overclocking: 20-25 MHz
+`define NRV_RESET_ADDR 32'h00820000 // Jump execution to SPI Flash (800000h, +128k(20000h) for FPGA bitstream)
+// tinyraytracer: 30 MHz RV32IM  electron 3:12
+//                20 MHz RV32IM  gracilis 3:44
+//                20 MHz RV32IMC gracilis 3:32
+//                25 MHz RV32IMC gracilis 2:49
+
+/************************* RAM (in bytes, needs to be a multiple of 4)***********************************************/
+
+// Using the 128 kbytes of single-ported RAM of the ice40-up5k
+// Note: cannot initialize it from .hex file, need to run from SPI Flash
+
+`define ICE40UP5K_SPRAM
+`define NRV_RAM 131072 
+
+// (other option, the 12 kbytes of BRAM, this one can be initialized from .hex file).
+//`define NRV_RAM 12288
+
+/************************* Advanced devices configuration *********************************************************/
+
+`define NRV_RUN_FROM_SPI_FLASH // Do not 'readmemh()' firmware from '.hex' file
+`define NRV_IO_HARDWARE_CONFIG // Comment-out to disable hardware config registers mapped in IO-Space
+                               // (only if you use your own firmware, libfemtorv32 depends on it)
+
+/******************************************************************************************************************/
+
+`define NRV_CONFIGURED

FemtoRV/RTL/DEVICES/MappedSPIFlash.v

@@ -51,6 +51,12 @@
  `define SPI_FLASH_CONFIGURED
 `endif
 
+`ifdef ICE_SUGAR
+ `define SPI_FLASH_FAST_READ_DUAL_IO
+ `define SPI_FLASH_DUMMY_CLOCKS 4 // Winbond SPI chips on icebreaker uses 4 dummy clocks
+ `define SPI_FLASH_CONFIGURED
+`endif
+
 `ifdef ULX3S
  `define SPI_FLASH_FAST_READ // TODO check whether dual IO mode can be done / dummy clocks
  `define SPI_FLASH_CONFIGURED

FemtoRV/RTL/femtosoc_config.v

@@ -16,6 +16,10 @@
 `include "CONFIGS/icebreaker_config.v"
 `endif
 
+`ifdef ICE_SUGAR
+`include "CONFIGS/icesugar_config.v"
+`endif
+
 `ifdef ECP5_EVN
 `include "CONFIGS/ecp5evn_config.v"
 `endif
@@ -80,6 +84,7 @@
 
 `ifdef ICE_SUGAR
  `define ICE40
+ `define PASSTHROUGH_PLL
 `endif
 
 `ifdef ICE_SUGAR_NANO

FemtoRV/RTL/get_config.v

@@ -44,6 +44,9 @@ initial begin
 `endif
 `ifdef ICE_BREAKER
    $write(" -DICE_BREAKER=1");   
+`endif
+`ifdef ICE_SUGAR
+   $write(" -DICE_SUGAR=1");
 `endif
    $write("\n");