mongoose/mip/driver_stm32.c
2022-06-13 01:04:09 +01:00

150 lines
6.2 KiB
C

// Copyright (c) 2022 Cesanta Software Limited
// All rights reserved
#include "mip.h"
#if MG_ENABLE_MIP && defined(__arm__)
struct stm32_eth {
uint32_t MACCR, MACFFR, MACHTHR, MACHTLR, MACMIIAR, MACMIIDR, MACFCR,
MACVLANTR, RESERVED0[2], MACRWUFFR, MACPMTCSR, RESERVED1, MACDBGR, MACSR,
MACIMR, MACA0HR, MACA0LR, MACA1HR, MACA1LR, MACA2HR, MACA2LR, MACA3HR,
MACA3LR, RESERVED2[40], MMCCR, MMCRIR, MMCTIR, MMCRIMR, MMCTIMR,
RESERVED3[14], MMCTGFSCCR, MMCTGFMSCCR, RESERVED4[5], MMCTGFCR,
RESERVED5[10], MMCRFCECR, MMCRFAECR, RESERVED6[10], MMCRGUFCR,
RESERVED7[334], PTPTSCR, PTPSSIR, PTPTSHR, PTPTSLR, PTPTSHUR, PTPTSLUR,
PTPTSAR, PTPTTHR, PTPTTLR, RESERVED8, PTPTSSR, PTPPPSCR, RESERVED9[564],
DMABMR, DMATPDR, DMARPDR, DMARDLAR, DMATDLAR, DMASR, DMAOMR, DMAIER,
DMAMFBOCR, DMARSWTR, RESERVED10[8], DMACHTDR, DMACHRDR, DMACHTBAR,
DMACHRBAR;
};
#define ETH ((struct stm32_eth *) (uintptr_t) 0x40028000)
#define BIT(x) ((uint32_t) 1 << (x))
#define ETH_PKT_SIZE 1540 // Max frame size
#define ETH_DESC_CNT 4 // Descriptors count
#define ETH_DS 4 // Descriptor size (words)
static uint32_t s_rxdesc[ETH_DESC_CNT][ETH_DS]; // RX descriptors
static uint32_t s_txdesc[ETH_DESC_CNT][ETH_DS]; // TX descriptors
static uint8_t s_rxbuf[ETH_DESC_CNT][ETH_PKT_SIZE]; // RX ethernet buffers
static uint8_t s_txbuf[ETH_DESC_CNT][ETH_PKT_SIZE]; // TX ethernet buffers
static void (*s_rx)(void *, size_t, void *); // Recv callback
static void *s_rxdata; // Recv callback data
static void *s_userdata; // Driver data
enum { PHY_ADDR = 0, PHY_BCR = 0, PHY_BSR = 1 }; // PHY constants
static inline void spin(volatile uint32_t count) {
while (count--) asm("nop");
}
static uint32_t eth_read_phy(uint8_t addr, uint8_t reg) {
ETH->MACMIIAR &= (7 << 2);
ETH->MACMIIAR |= ((uint32_t) addr << 11) | ((uint32_t) reg << 6);
ETH->MACMIIAR |= BIT(0);
while (ETH->MACMIIAR & BIT(0)) spin(1);
return ETH->MACMIIDR;
}
static void eth_write_phy(uint8_t addr, uint8_t reg, uint32_t val) {
ETH->MACMIIDR = val;
ETH->MACMIIAR &= (7 << 2);
ETH->MACMIIAR |= ((uint32_t) addr << 11) | ((uint32_t) reg << 6) | BIT(1);
ETH->MACMIIAR |= BIT(0);
while (ETH->MACMIIAR & BIT(0)) spin(1);
}
static void mip_driver_stm32_init(void *userdata) {
s_userdata = userdata;
// Init RX descriptors
for (int i = 0; i < ETH_DESC_CNT; i++) {
s_rxdesc[i][0] = BIT(31); // Own
s_rxdesc[i][1] = sizeof(s_rxbuf[i]) | BIT(14); // 2nd address chained
s_rxdesc[i][2] = (uint32_t) (uintptr_t) s_rxbuf[i]; // Point to data buffer
s_rxdesc[i][3] =
(uint32_t) (uintptr_t) s_rxdesc[(i + 1) % ETH_DESC_CNT]; // Chain
}
// Init TX descriptors
for (int i = 0; i < ETH_DESC_CNT; i++) {
s_txdesc[i][2] = (uint32_t) (uintptr_t) s_txbuf[i]; // Buf pointer
s_txdesc[i][3] =
(uint32_t) (uintptr_t) s_txdesc[(i + 1) % ETH_DESC_CNT]; // Chain
}
ETH->DMABMR |= BIT(0); // Software reset
while ((ETH->DMABMR & BIT(0)) != 0) spin(1); // Wait until done
// NOTE(cpq): we do not use extended descriptor bit 7, and do not use
// hardware checksum. Therefore, descriptor size is 4, not 8
// ETH->DMABMR = BIT(13) | BIT(16) | BIT(22) | BIT(23) | BIT(25);
ETH->MACIMR = BIT(3) | BIT(9); // Mask timestamp & PMT IT
ETH->MACMIIAR = 4 << 2; // MDC clock 150-216 MHz, 38.8.1
ETH->MACFCR = BIT(7); // Disable zero quarta pause
ETH->MACFFR = BIT(31); // Receive all
eth_write_phy(PHY_ADDR, PHY_BCR, BIT(15)); // Reset PHY
eth_write_phy(PHY_ADDR, PHY_BCR, BIT(12)); // Set autonegotiation
ETH->DMARDLAR = (uint32_t) (uintptr_t) s_rxdesc; // RX descriptors
ETH->DMATDLAR = (uint32_t) (uintptr_t) s_txdesc; // RX descriptors
ETH->DMAIER = BIT(6) | BIT(16); // RIE, NISE
ETH->MACCR = BIT(2) | BIT(3) | BIT(11) | BIT(14); // RE, TE, Duplex, Fast
ETH->DMAOMR = BIT(1) | BIT(13) | BIT(21) | BIT(25); // SR, ST, TSF, RSF
}
static void mip_driver_stm32_setrx(void (*rx)(void *, size_t, void *),
void *rxdata) {
s_rx = rx;
s_rxdata = rxdata;
}
static uint32_t s_txno;
static size_t mip_driver_stm32_tx(const void *buf, size_t len, void *userdata) {
if (len > sizeof(s_txbuf[s_txno])) {
printf("%s: frame too big, %ld\n", __func__, (long) len);
len = 0; // Frame is too big
} else if ((s_txdesc[s_txno][0] & BIT(31))) {
printf("%s: no free descr\n", __func__);
len = 0; // All descriptors are busy, fail
} else {
memcpy(s_txbuf[s_txno], buf, len); // Copy data
s_txdesc[s_txno][1] = (uint32_t) len; // Set data len
s_txdesc[s_txno][0] = BIT(20) | BIT(28) | BIT(29) | BIT(30); // Chain,FS,LS
s_txdesc[s_txno][0] |= BIT(31); // Set OWN bit - let DMA take over
if (++s_txno >= ETH_DESC_CNT) s_txno = 0;
}
uint32_t sr = ETH->DMASR;
if (sr & BIT(2)) ETH->DMASR = BIT(2), ETH->DMATPDR = 0; // Resume
if (sr & BIT(5)) ETH->DMASR = BIT(5), ETH->DMATPDR = 0; // if busy
if (len == 0) printf("E: D0 %lx SR %lx\n", (long) s_txdesc[0][0], (long) sr);
return len;
(void) userdata;
}
static bool mip_driver_stm32_status(void *userdata) {
uint32_t bsr = eth_read_phy(PHY_ADDR, PHY_BSR);
return bsr & BIT(2) ? 1 : 0;
(void) userdata;
}
void ETH_IRQHandler(void);
void ETH_IRQHandler(void) {
volatile uint32_t sr = ETH->DMASR;
if (sr & BIT(6)) { // Frame received, loop
for (uint32_t i = 0; i < ETH_DESC_CNT; i++) {
if (s_rxdesc[i][0] & BIT(31)) continue;
uint32_t len = ((s_rxdesc[i][0] >> 16) & (BIT(14) - 1));
// printf("%lx %lu %lx %lx\n", i, len, s_rxdesc[i][0], sr);
if (s_rx != NULL) s_rx(s_rxbuf[i], len > 4 ? len - 4 : len, s_rxdata);
s_rxdesc[i][0] = BIT(31);
}
}
if (sr & BIT(7)) ETH->DMARPDR = 0; // Resume RX
ETH->DMASR = sr & ~(BIT(2) | BIT(7)); // Clear status
}
struct mip_driver mip_driver_stm32 = {.init = mip_driver_stm32_init,
.tx = mip_driver_stm32_tx,
.rxcb = mip_driver_stm32_setrx,
.status = mip_driver_stm32_status};
#endif // MG_ENABLE_MIP