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Merging pull request #37 Adds hard-float support to stm32f4, with a nice mandelbrot example

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Merge remote-tracking branch 'schodet/hard-float'
This commit is contained in:
Piotr Esden-Tempski
2012-10-05 13:03:58 -07:00
parent 4efa64c278 aac5909ff1
commit cb60e37608
7 changed files with 243 additions and 3 deletions
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5
examples/stm32/f4/Makefile.include
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@@ -36,12 +36,13 @@ endif
TOOLCHAIN_DIR := ../../../../..
endif
CFLAGS += -Os -g -Wall -Wextra -I$(TOOLCHAIN_DIR)/include \
-fno-common -mcpu=cortex-m4 -mthumb -msoft-float -MD -DSTM32F4
-fno-common -mcpu=cortex-m4 -mthumb \
-mfloat-abi=hard -mfpu=fpv4-sp-d16 -MD -DSTM32F4
LDSCRIPT ?= $(BINARY).ld
LDFLAGS += --static -lc -lnosys -L$(TOOLCHAIN_DIR)/lib \
-L$(TOOLCHAIN_DIR)/lib/stm32/f4 \
-T$(LDSCRIPT) -nostartfiles -Wl,--gc-sections \
-mthumb -mcpu=cortex-m4 -march=armv7 -mfix-cortex-m3-ldrd -msoft-float
-mthumb -mcpu=cortex-m4 -mthumb -mfloat-abi=hard -mfpu=fpv4-sp-d16
OBJS += $(BINARY).o
OOCD ?= openocd

25
examples/stm32/f4/stm32f4-discovery/mandelbrot/Makefile Normal file
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@@ -0,0 +1,25 @@
##
## This file is part of the libopencm3 project.
##
## Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
##
## This library is free software: you can redistribute it and/or modify
## it under the terms of the GNU Lesser General Public License as published by
## the Free Software Foundation, either version 3 of the License, or
## (at your option) any later version.
##
## This library is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
## GNU Lesser General Public License for more details.
##
## You should have received a copy of the GNU Lesser General Public License
## along with this library. If not, see <http://www.gnu.org/licenses/>.
##
BINARY = mandel
LDSCRIPT = ../stm32f4-discovery.ld
include ../../Makefile.include

12
examples/stm32/f4/stm32f4-discovery/mandelbrot/README Normal file
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@@ -0,0 +1,12 @@
------------------------------------------------------------------------------
README
------------------------------------------------------------------------------
This example program demonstrates the floating point coprocessor usage on
the ST STM32F4DISCOVERY eval board.
A mandelbrot fractal is calculated and sent as "ascii-art" image through
the USART2.
The terminal settings for the receiving device/PC are 38400 8n1.

127
examples/stm32/f4/stm32f4-discovery/mandelbrot/mandel.c Normal file
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@@ -0,0 +1,127 @@
/*
* This file is part of the libopencm3 project.
*
* Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
* Copyright (C) 2011 Stephen Caudle <scaudle@doceme.com>
* Copyright (C) 2012 Daniel Serpell <daniel.serpell@gmail.com>
*
* This library is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include <libopencm3/stm32/f4/rcc.h>
#include <libopencm3/stm32/f4/gpio.h>
#include <libopencm3/stm32/usart.h>
void clock_setup(void)
{
/* Enable high-speed clock at 120MHz */
rcc_clock_setup_hse_3v3(&hse_8mhz_3v3[CLOCK_3V3_120MHZ]);
/* Enable GPIOD clock for LED & USARTs. */
rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPDEN);
rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPAEN);
/* Enable clocks for USART2. */
rcc_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_USART2EN);
}
void usart_setup(void)
{
/* Setup USART2 parameters. */
usart_set_baudrate(USART2, 38400);
usart_set_databits(USART2, 8);
usart_set_stopbits(USART2, USART_STOPBITS_1);
usart_set_mode(USART2, USART_MODE_TX);
usart_set_parity(USART2, USART_PARITY_NONE);
usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE);
/* Finally enable the USART. */
usart_enable(USART2);
}
void gpio_setup(void)
{
/* Setup GPIO pin GPIO12 on GPIO port D for LED. */
gpio_mode_setup(GPIOD, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO12);
/* Setup GPIO pins for USART2 transmit. */
gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO2);
/* Setup USART2 TX pin as alternate function. */
gpio_set_af(GPIOA, GPIO_AF7, GPIO2);
}
/* Maximum number of iterations for the escape-time calculation */
#define maxIter 32
/* This array converts the iteration count to a character representation. */
static char color[maxIter+1] = " .:++xxXXX%%%%%%################";
/* Main mandelbrot calculation */
static int iterate(float px, float py)
{
int it=0;
float x=0,y=0;
while(it<maxIter)
{
float nx = x*x;
float ny = y*y;
if( (nx + ny) > 4 )
return it;
// Zn+1 = Zn^2 + P
y = 2*x*y + py;
x = nx - ny + px;
it++;
}
return 0;
}
static void mandel(float cX, float cY, float scale)
{
int x,y;
for(x=-60;x<60;x++)
{
for(y=-50;y<50;y++)
{
int i = iterate(cX+x*scale, cY+y*scale);
usart_send_blocking(USART2, color[i]);
}
usart_send_blocking(USART2, '\r');
usart_send_blocking(USART2, '\n');
}
}
int main(void)
{
float scale = 0.25f, centerX = -0.5f, centerY = 0.0f;
clock_setup();
gpio_setup();
usart_setup();
while (1) {
/* Blink the LED (PD12) on the board with each fractal drawn. */
gpio_toggle(GPIOD, GPIO12); /* LED on/off */
mandel(centerX,centerY,scale); /* draw mandelbrot */
/* Change scale and center */
centerX += 0.175f * scale;
centerY += 0.522f * scale;
scale *= 0.875f;
usart_send_blocking(USART2, '\r');
usart_send_blocking(USART2, '\n');
}
return 0;
}

69
include/libopencm3/stm32/f4/scb.h
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@@ -72,6 +72,63 @@
/* AFSR: Auxiliary Fault Status Register */
#define SCB_AFSR MMIO32(SCB_BASE + 0x3C)
/* ID_PFR0: Processor Feature Register 0 */
#define SCB_ID_PFR0 MMIO32(SCB_BASE + 0x40)
/* ID_PFR1: Processor Feature Register 1 */
#define SCB_ID_PFR1 MMIO32(SCB_BASE + 0x44)
/* ID_DFR0: Debug Features Register 0 */
#define SCB_ID_DFR0 MMIO32(SCB_BASE + 0x48)
/* ID_AFR0: Auxiliary Features Register 0 */
#define SCB_ID_AFR0 MMIO32(SCB_BASE + 0x4C)
/* ID_MMFR0: Memory Model Feature Register 0 */
#define SCB_ID_MMFR0 MMIO32(SCB_BASE + 0x50)
/* ID_MMFR1: Memory Model Feature Register 1 */
#define SCB_ID_MMFR1 MMIO32(SCB_BASE + 0x54)
/* ID_MMFR2: Memory Model Feature Register 2 */
#define SCB_ID_MMFR2 MMIO32(SCB_BASE + 0x58)
/* ID_MMFR3: Memory Model Feature Register 3 */
#define SCB_ID_MMFR3 MMIO32(SCB_BASE + 0x5C)
/* ID_ISAR0: Instruction Set Attributes Register 0 */
#define SCB_ID_ISAR0 MMIO32(SCB_BASE + 0x60)
/* ID_ISAR1: Instruction Set Attributes Register 1 */
#define SCB_ID_ISAR1 MMIO32(SCB_BASE + 0x64)
/* ID_ISAR2: Instruction Set Attributes Register 2 */
#define SCB_ID_ISAR2 MMIO32(SCB_BASE + 0x68)
/* ID_ISAR3: Instruction Set Attributes Register 3 */
#define SCB_ID_ISAR3 MMIO32(SCB_BASE + 0x6C)
/* ID_ISAR4: Instruction Set Attributes Register 4 */
#define SCB_ID_ISAR4 MMIO32(SCB_BASE + 0x70)
/* CPACR: Coprocessor Access Control Register */
#define SCB_CPACR MMIO32(SCB_BASE + 0x88)
/* FPCCR: Floating-Point Context Control Register */
#define SCB_FPCCR MMIO32(SCB_BASE + 0x234)
/* FPCAR: Floating-Point Context Address Register */
#define SCB_FPCAR MMIO32(SCB_BASE + 0x238)
/* FPDSCR: Floating-Point Default Status Control Register */
#define SCB_FPDSCR MMIO32(SCB_BASE + 0x23C)
/* MVFR0: Media and Floating-Point Feature Register 0 */
#define SCB_MVFR0 MMIO32(SCB_BASE + 0x240)
/* MVFR1: Media and Floating-Point Feature Register 1 */
#define SCB_MVFR1 MMIO32(SCB_BASE + 0x244)
/* --- SCB values ---------------------------------------------------------- */
/* --- SCB_CPUID values ---------------------------------------------------- */
@@ -292,6 +349,18 @@
/* BFAR [31:0]: Bus fault address */
/* --- SCB_CPACR values ---------------------------------------------------- */
/* CPACR CPn: Access privileges values */
#define SCB_CPACR_NONE 0 /* Access denied */
#define SCB_CPACR_PRIV 1 /* Privileged access only */
#define SCB_CPACR_FULL 3 /* Full access */
/* CPACR [20:21]: Access privileges for coprocessor 10 */
#define SCB_CPACR_CP10 (1 << 20)
/* CPACR [22:23]: Access privileges for coprocessor 11 */
#define SCB_CPACR_CP11 (1 << 22)
/* --- SCB functions ------------------------------------------------------- */
BEGIN_DECLS

3
lib/stm32/f4/Makefile
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@@ -24,7 +24,8 @@ PREFIX ?= arm-none-eabi
CC = $(PREFIX)-gcc
AR = $(PREFIX)-ar
CFLAGS = -Os -g -Wall -Wextra -I../../../include -fno-common \
-mcpu=cortex-m3 -mthumb -Wstrict-prototypes \
-mcpu=cortex-m4 -mthumb -mfloat-abi=hard -mfpu=fpv4-sp-d16 \
-Wstrict-prototypes \
-ffunction-sections -fdata-sections -MD -DSTM32F4
# ARFLAGS = rcsv
ARFLAGS = rcs

5
lib/stm32/f4/vector.c
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@@ -18,6 +18,8 @@
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include <libopencm3/stm32/f4/scb.h>
#define WEAK __attribute__ ((weak))
/* Symbols exported by the linker script(s): */
@@ -224,6 +226,9 @@ void reset_handler(void)
__asm__("MSR msp, %0" : : "r"(&_stack));
/* Enable access to Floating-Point coprocessor. */
SCB_CPACR |= SCB_CPACR_FULL * (SCB_CPACR_CP10 | SCB_CPACR_CP11);
for (src = &_data_loadaddr, dest = &_data; dest < &_edata; src++, dest++)
*dest = *src;