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Diffstat (limited to 'example/sys.c')
-rw-r--r-- | example/sys.c | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/example/sys.c b/example/sys.c new file mode 100644 index 0000000..1e6c030 --- /dev/null +++ b/example/sys.c @@ -0,0 +1,600 @@ +/* + * sys.c - system routines for the initial page for STM32F103. + * + * Copyright (C) 2013 Flying Stone Technology + * Author: NIIBE Yutaka <gniibe@fsij.org> + * + * Copying and distribution of this file, with or without modification, + * are permitted in any medium without royalty provided the copyright + * notice and this notice are preserved. This file is offered as-is, + * without any warranty. + * + * When the flash ROM is protected, we cannot modify the initial page. + * We put some system routines (which is useful for any program) here. + */ + +#include <stdint.h> +#include <stdlib.h> +#include "board.h" + + +#define CORTEX_PRIORITY_BITS 4 +#define CORTEX_PRIORITY_MASK(n) ((n) << (8 - CORTEX_PRIORITY_BITS)) +#define USB_LP_CAN1_RX0_IRQn 20 +#define STM32_USB_IRQ_PRIORITY 11 + +#define FLASH_PAGE_SIZE 1024 + + + +#define STM32_SW_PLL (2 << 0) +#define STM32_PLLSRC_HSE (1 << 16) + +#define STM32_PLLXTPRE_DIV1 (0 << 17) +#define STM32_PLLXTPRE_DIV2 (1 << 17) + +#define STM32_HPRE_DIV1 (0 << 4) + +#define STM32_PPRE1_DIV2 (4 << 8) + +#define STM32_PPRE2_DIV1 (0 << 11) +#define STM32_PPRE2_DIV2 (4 << 11) + +#define STM32_ADCPRE_DIV4 (1 << 14) +#define STM32_ADCPRE_DIV6 (2 << 14) + +#define STM32_USBPRE_DIV1P5 (0 << 22) + +#define STM32_MCO_NOCLOCK (0 << 24) + +#define STM32_SW STM32_SW_PLL +#define STM32_PLLSRC STM32_PLLSRC_HSE +#define STM32_HPRE STM32_HPRE_DIV1 +#define STM32_PPRE1 STM32_PPRE1_DIV2 +#define STM32_PPRE2 STM32_PPRE2_DIV1 +#define STM32_ADCPRE STM32_ADCPRE_DIV6 +#define STM32_MCOSEL STM32_MCO_NOCLOCK +#define STM32_USBPRE STM32_USBPRE_DIV1P5 + +#define STM32_PLLCLKIN (STM32_HSECLK / 1) +#define STM32_PLLMUL ((STM32_PLLMUL_VALUE - 2) << 18) +#define STM32_PLLCLKOUT (STM32_PLLCLKIN * STM32_PLLMUL_VALUE) +#define STM32_SYSCLK STM32_PLLCLKOUT +#define STM32_HCLK (STM32_SYSCLK / 1) + +#define STM32_FLASHBITS 0x00000012 + +struct NVIC { + uint32_t ISER[8]; + uint32_t unused1[24]; + uint32_t ICER[8]; + uint32_t unused2[24]; + uint32_t ISPR[8]; + uint32_t unused3[24]; + uint32_t ICPR[8]; + uint32_t unused4[24]; + uint32_t IABR[8]; + uint32_t unused5[56]; + uint32_t IPR[60]; +}; + +#define NVICBase ((struct NVIC *)0xE000E100) +#define NVIC_ISER(n) (NVICBase->ISER[n]) +#define NVIC_ICPR(n) (NVICBase->ICPR[n]) +#define NVIC_IPR(n) (NVICBase->IPR[n]) + +static void +nvic_enable_vector (uint32_t n, uint32_t prio) +{ + unsigned int sh = (n & 3) << 3; + + NVIC_IPR (n >> 2) = (NVIC_IPR(n >> 2) & ~(0xFF << sh)) | (prio << sh); + NVIC_ICPR (n >> 5) = 1 << (n & 0x1F); + NVIC_ISER (n >> 5) = 1 << (n & 0x1F); +} + + +#define PERIPH_BASE 0x40000000 +#define APB2PERIPH_BASE (PERIPH_BASE + 0x10000) +#define AHBPERIPH_BASE (PERIPH_BASE + 0x20000) + +struct RCC { + volatile uint32_t CR; + volatile uint32_t CFGR; + volatile uint32_t CIR; + volatile uint32_t APB2RSTR; + volatile uint32_t APB1RSTR; + volatile uint32_t AHBENR; + volatile uint32_t APB2ENR; + volatile uint32_t APB1ENR; + volatile uint32_t BDCR; + volatile uint32_t CSR; +}; + +#define RCC_BASE (AHBPERIPH_BASE + 0x1000) +#define RCC ((struct RCC *)RCC_BASE) + +#define RCC_APB1ENR_USBEN 0x00800000 +#define RCC_APB1RSTR_USBRST 0x00800000 + +#define RCC_CR_HSION 0x00000001 +#define RCC_CR_HSIRDY 0x00000002 +#define RCC_CR_HSITRIM 0x000000F8 +#define RCC_CR_HSEON 0x00010000 +#define RCC_CR_HSERDY 0x00020000 +#define RCC_CR_PLLON 0x01000000 +#define RCC_CR_PLLRDY 0x02000000 + +#define RCC_CFGR_SWS 0x0000000C +#define RCC_CFGR_SWS_HSI 0x00000000 + +#define RCC_AHBENR_CRCEN 0x0040 + +struct FLASH { + volatile uint32_t ACR; + volatile uint32_t KEYR; + volatile uint32_t OPTKEYR; + volatile uint32_t SR; + volatile uint32_t CR; + volatile uint32_t AR; + volatile uint32_t RESERVED; + volatile uint32_t OBR; + volatile uint32_t WRPR; +}; + +#define FLASH_R_BASE (AHBPERIPH_BASE + 0x2000) +#define FLASH ((struct FLASH *) FLASH_R_BASE) + +static void +clock_init (void) +{ + /* HSI setup */ + RCC->CR |= RCC_CR_HSION; + while (!(RCC->CR & RCC_CR_HSIRDY)) + ; + RCC->CR &= RCC_CR_HSITRIM | RCC_CR_HSION; + RCC->CFGR = 0; + while ((RCC->CFGR & RCC_CFGR_SWS) != RCC_CFGR_SWS_HSI) + ; + + /* HSE setup */ + RCC->CR |= RCC_CR_HSEON; + while (!(RCC->CR & RCC_CR_HSERDY)) + ; + + /* PLL setup */ + RCC->CFGR |= STM32_PLLMUL | STM32_PLLXTPRE | STM32_PLLSRC; + RCC->CR |= RCC_CR_PLLON; + while (!(RCC->CR & RCC_CR_PLLRDY)) + ; + + /* Clock settings */ + RCC->CFGR = STM32_MCOSEL | STM32_USBPRE | STM32_PLLMUL | STM32_PLLXTPRE + | STM32_PLLSRC | STM32_ADCPRE | STM32_PPRE2 | STM32_PPRE1 | STM32_HPRE; + + /* Flash setup */ + FLASH->ACR = STM32_FLASHBITS; + + /* CRC */ + RCC->AHBENR |= RCC_AHBENR_CRCEN; + + /* Switching on the configured clock source. */ + RCC->CFGR |= STM32_SW; + while ((RCC->CFGR & RCC_CFGR_SWS) != (STM32_SW << 2)) + ; +} + +#define RCC_APB2ENR_IOPAEN 0x00000004 +#define RCC_APB2RSTR_IOPARST 0x00000004 +#define RCC_APB2ENR_IOPBEN 0x00000008 +#define RCC_APB2RSTR_IOPBRST 0x00000008 +#define RCC_APB2ENR_IOPCEN 0x00000010 +#define RCC_APB2RSTR_IOPCRST 0x00000010 +#define RCC_APB2ENR_IOPDEN 0x00000020 +#define RCC_APB2RSTR_IOPDRST 0x00000020 + + +struct GPIO { + volatile uint32_t CRL; + volatile uint32_t CRH; + volatile uint32_t IDR; + volatile uint32_t ODR; + volatile uint32_t BSRR; + volatile uint32_t BRR; + volatile uint32_t LCKR; +}; + +#define GPIOA_BASE (APB2PERIPH_BASE + 0x0800) +#define GPIOA ((struct GPIO *) GPIOA_BASE) +#define GPIOB_BASE (APB2PERIPH_BASE + 0x0C00) +#define GPIOB ((struct GPIO *) GPIOB_BASE) +#define GPIOC_BASE (APB2PERIPH_BASE + 0x1000) +#define GPIOC ((struct GPIO *) GPIOC_BASE) +#define GPIOD_BASE (APB2PERIPH_BASE + 0x1400) +#define GPIOD ((struct GPIO *) GPIOD_BASE) +#define GPIOE_BASE (APB2PERIPH_BASE + 0x1800) +#define GPIOE ((struct GPIO *) GPIOE_BASE) + +#define GPIO_USB ((struct GPIO *) GPIO_USB_BASE) +#define GPIO_LED ((struct GPIO *) GPIO_LED_BASE) + +static void +gpio_init (void) +{ + /* Enable GPIO clock. */ + RCC->APB2ENR |= RCC_APB2ENR_IOP_EN; + RCC->APB2RSTR = RCC_APB2RSTR_IOP_RST; + RCC->APB2RSTR = 0; + + GPIO_USB->ODR = VAL_GPIO_ODR; + GPIO_USB->CRH = VAL_GPIO_CRH; + GPIO_USB->CRL = VAL_GPIO_CRL; + +#if GPIO_USB_BASE != GPIO_LED_BASE + GPIO_LED->ODR = VAL_GPIO_LED_ODR; + GPIO_LED->CRH = VAL_GPIO_LED_CRH; + GPIO_LED->CRL = VAL_GPIO_LED_CRL; +#endif +} + +static void +usb_cable_config (int enable) +{ +#if defined(GPIO_USB_SET_TO_ENABLE) + if (enable) + GPIO_USB->BSRR = (1 << GPIO_USB_SET_TO_ENABLE); + else + GPIO_USB->BRR = (1 << GPIO_USB_SET_TO_ENABLE); +#elif defined(GPIO_USB_CLEAR_TO_ENABLE) + if (enable) + GPIO_USB->BRR = (1 << GPIO_USB_CLEAR_TO_ENABLE); + else + GPIO_USB->BSRR = (1 << GPIO_USB_CLEAR_TO_ENABLE); +#else + (void)enable; +#endif +} + +void +set_led (int on) +{ +#if defined(GPIO_LED_CLEAR_TO_EMIT) + if (on) + GPIO_LED->BRR = (1 << GPIO_LED_CLEAR_TO_EMIT); + else + GPIO_LED->BSRR = (1 << GPIO_LED_CLEAR_TO_EMIT); +#else + if (on) + GPIO_LED->BSRR = (1 << GPIO_LED_SET_TO_EMIT); + else + GPIO_LED->BRR = (1 << GPIO_LED_SET_TO_EMIT); +#endif +} + +static void wait (int count) +{ + int i; + + for (i = 0; i < count; i++) + asm volatile ("" : : "r" (i) : "memory"); +} + +#define USB_IRQ 20 +#define USB_IRQ_PRIORITY ((11) << 4) + +static void +usb_lld_sys_shutdown (void) +{ + RCC->APB1ENR &= ~RCC_APB1ENR_USBEN; + RCC->APB1RSTR = RCC_APB1RSTR_USBRST; + usb_cable_config (0); +} + +static void +usb_lld_sys_init (void) +{ + if ((RCC->APB1ENR & RCC_APB1ENR_USBEN) + && (RCC->APB1RSTR & RCC_APB1RSTR_USBRST) == 0) + /* Make sure the device is disconnected, even after core reset. */ + { + usb_lld_sys_shutdown (); + /* Disconnect requires SE0 (>= 2.5uS). */ + wait (300); + } + + usb_cable_config (1); + RCC->APB1ENR |= RCC_APB1ENR_USBEN; + nvic_enable_vector (USB_LP_CAN1_RX0_IRQn, + CORTEX_PRIORITY_MASK (STM32_USB_IRQ_PRIORITY)); + /* + * Note that we also have other IRQ(s): + * USB_HP_CAN1_TX_IRQn (for double-buffered or isochronous) + * USBWakeUp_IRQn (suspend/resume) + */ + RCC->APB1RSTR = RCC_APB1RSTR_USBRST; + RCC->APB1RSTR = 0; +} + +#define FLASH_KEY1 0x45670123UL +#define FLASH_KEY2 0xCDEF89ABUL + +enum flash_status +{ + FLASH_BUSY = 1, + FLASH_ERROR_PG, + FLASH_ERROR_WRP, + FLASH_COMPLETE, + FLASH_TIMEOUT +}; + +static void __attribute__ ((used)) +flash_unlock (void) +{ + FLASH->KEYR = FLASH_KEY1; + FLASH->KEYR = FLASH_KEY2; +} + + +#define intr_disable() asm volatile ("cpsid i" : : : "memory") + +#define intr_enable() asm volatile ("msr BASEPRI, %0\n\t" \ + "cpsie i" : : "r" (0) : "memory") + +#define FLASH_SR_BSY 0x01 +#define FLASH_SR_PGERR 0x04 +#define FLASH_SR_WRPRTERR 0x10 +#define FLASH_SR_EOP 0x20 + +#define FLASH_CR_PG 0x0001 +#define FLASH_CR_PER 0x0002 +#define FLASH_CR_MER 0x0004 +#define FLASH_CR_OPTPG 0x0010 +#define FLASH_CR_OPTER 0x0020 +#define FLASH_CR_STRT 0x0040 +#define FLASH_CR_LOCK 0x0080 +#define FLASH_CR_OPTWRE 0x0200 +#define FLASH_CR_ERRIE 0x0400 +#define FLASH_CR_EOPIE 0x1000 + +static int +flash_wait_for_last_operation (uint32_t timeout) +{ + int status; + + do + { + status = FLASH->SR; + if (--timeout == 0) + break; + } + while ((status & FLASH_SR_BSY) != 0); + + return status & (FLASH_SR_BSY|FLASH_SR_PGERR|FLASH_SR_WRPRTERR); +} + +#define FLASH_PROGRAM_TIMEOUT 0x00010000 +#define FLASH_ERASE_TIMEOUT 0x01000000 + +static int +flash_program_halfword (uint32_t addr, uint16_t data) +{ + int status; + + status = flash_wait_for_last_operation (FLASH_PROGRAM_TIMEOUT); + + intr_disable (); + if (status == 0) + { + FLASH->CR |= FLASH_CR_PG; + + *(volatile uint16_t *)addr = data; + + status = flash_wait_for_last_operation (FLASH_PROGRAM_TIMEOUT); + FLASH->CR &= ~FLASH_CR_PG; + } + intr_enable (); + + return status; +} + +static int +flash_erase_page (uint32_t addr) +{ + int status; + + status = flash_wait_for_last_operation (FLASH_ERASE_TIMEOUT); + + intr_disable (); + if (status == 0) + { + FLASH->CR |= FLASH_CR_PER; + FLASH->AR = addr; + FLASH->CR |= FLASH_CR_STRT; + + status = flash_wait_for_last_operation (FLASH_ERASE_TIMEOUT); + FLASH->CR &= ~FLASH_CR_PER; + } + intr_enable (); + + return status; +} + +static int +flash_check_blank (const uint8_t *p_start, size_t size) +{ + const uint8_t *p; + + for (p = p_start; p < p_start + size; p++) + if (*p != 0xff) + return 0; + + return 1; +} + +extern uint8_t __flash_start__, __flash_end__; + +static int +flash_write (uint32_t dst_addr, const uint8_t *src, size_t len) +{ + int status; + uint32_t flash_start = (uint32_t)&__flash_start__; + uint32_t flash_end = (uint32_t)&__flash_end__; + + if (dst_addr < flash_start || dst_addr + len > flash_end) + return 0; + + while (len) + { + uint16_t hw = *src++; + + hw |= (*src++ << 8); + status = flash_program_halfword (dst_addr, hw); + if (status != 0) + return 0; /* error return */ + + dst_addr += 2; + len -= 2; + } + + return 1; +} + +#define OPTION_BYTES_ADDR 0x1ffff800 + +static int +flash_protect (void) +{ + int status; + uint32_t option_bytes_value; + + status = flash_wait_for_last_operation (FLASH_ERASE_TIMEOUT); + + intr_disable (); + if (status == 0) + { + FLASH->OPTKEYR = FLASH_KEY1; + FLASH->OPTKEYR = FLASH_KEY2; + + FLASH->CR |= FLASH_CR_OPTER; + FLASH->CR |= FLASH_CR_STRT; + + status = flash_wait_for_last_operation (FLASH_ERASE_TIMEOUT); + FLASH->CR &= ~FLASH_CR_OPTER; + } + intr_enable (); + + if (status != 0) + return 0; + + option_bytes_value = *(uint32_t *)OPTION_BYTES_ADDR; + return (option_bytes_value & 0xff) == 0xff ? 1 : 0; +} + +static void __attribute__((naked)) +flash_erase_all_and_exec (void (*entry)(void)) +{ + uint32_t addr = (uint32_t)&__flash_start__; + uint32_t end = (uint32_t)&__flash_end__; + int r; + + while (addr < end) + { + r = flash_erase_page (addr); + if (r != 0) + break; + + addr += FLASH_PAGE_SIZE; + } + + if (addr >= end) + (*entry) (); + + for (;;); +} + +struct SCB +{ + volatile uint32_t CPUID; + volatile uint32_t ICSR; + volatile uint32_t VTOR; + volatile uint32_t AIRCR; + volatile uint32_t SCR; + volatile uint32_t CCR; + volatile uint8_t SHP[12]; + volatile uint32_t SHCSR; + volatile uint32_t CFSR; + volatile uint32_t HFSR; + volatile uint32_t DFSR; + volatile uint32_t MMFAR; + volatile uint32_t BFAR; + volatile uint32_t AFSR; + volatile uint32_t PFR[2]; + volatile uint32_t DFR; + volatile uint32_t ADR; + volatile uint32_t MMFR[4]; + volatile uint32_t ISAR[5]; +}; + +#define SCS_BASE (0xE000E000) +#define SCB_BASE (SCS_BASE + 0x0D00) +#define SCB ((struct SCB *) SCB_BASE) + +#define SYSRESETREQ 0x04 +static void +nvic_system_reset (void) +{ + SCB->AIRCR = (0x05FA0000 | (SCB->AIRCR & 0x70) | SYSRESETREQ); + asm volatile ("dsb"); +} + +static void __attribute__ ((naked)) +reset (void) +{ + asm volatile ("cpsid i\n\t" /* Mask all interrupts. */ + "mov.w r0, #0xed00\n\t" /* r0 = SCR */ + "movt r0, #0xe000\n\t" + "mov r1, pc\n\t" /* r1 = (PC + 0x1000) & ~0x0fff */ + "mov r2, #0x1000\n\t" + "add r1, r1, r2\n\t" + "sub r2, r2, #1\n\t" + "bic r1, r1, r2\n\t" + "str r1, [r0, #8]\n\t" /* Set SCR->VCR */ + "ldr r0, [r1], #4\n\t" + "msr MSP, r0\n\t" /* Main (exception handler) stack. */ + "ldr r0, [r1]\n\t" /* Reset handler. */ + "bx r0\n" + : /* no output */ : /* no input */ : "memory"); +} + +typedef void (*handler)(void); +extern uint8_t __ram_end__; + +extern const unsigned long *FT0, *FT1, *FT2; + +handler vector[] __attribute__ ((section(".vectors"))) = { + (handler)&__ram_end__, + reset, + (handler)set_led, + flash_unlock, + (handler)flash_program_halfword, + (handler)flash_erase_page, + (handler)flash_check_blank, + (handler)flash_write, + (handler)flash_protect, + (handler)flash_erase_all_and_exec, + usb_lld_sys_init, + usb_lld_sys_shutdown, + nvic_system_reset, + clock_init, + gpio_init, + (handler)&FT0, + (handler)&FT1, + (handler)&FT2, +}; + +const uint8_t sys_version[8] __attribute__((section(".sys.version"))) = { + 3*2+2, /* bLength */ + 0x03, /* bDescriptorType = USB_STRING_DESCRIPTOR_TYPE*/ + /* sys version: "2.0" */ + '2', 0, '.', 0, '0', 0, +}; |