Files
mongoose/src/drivers/tm4c.c
T

273 lines
11 KiB
C

#include "net_builtin.h"
#if MG_ENABLE_TCPIP && defined(MG_ENABLE_DRIVER_TM4C) && MG_ENABLE_DRIVER_TM4C
struct tm4c_emac {
volatile uint32_t EMACCFG, EMACFRAMEFLTR, EMACHASHTBLH, EMACHASHTBLL,
EMACMIIADDR, EMACMIIDATA, EMACFLOWCTL, EMACVLANTG, RESERVED0, EMACSTATUS,
EMACRWUFF, EMACPMTCTLSTAT, RESERVED1[2], EMACRIS, EMACIM, EMACADDR0H,
EMACADDR0L, EMACADDR1H, EMACADDR1L, EMACADDR2H, EMACADDR2L, EMACADDR3H,
EMACADDR3L, RESERVED2[31], EMACWDOGTO, RESERVED3[8], EMACMMCCTRL,
EMACMMCRXRIS, EMACMMCTXRIS, EMACMMCRXIM, EMACMMCTXIM, RESERVED4,
EMACTXCNTGB, RESERVED5[12], EMACTXCNTSCOL, EMACTXCNTMCOL, RESERVED6[4],
EMACTXOCTCNTG, RESERVED7[6], EMACRXCNTGB, RESERVED8[4], EMACRXCNTCRCERR,
EMACRXCNTALGNERR, RESERVED9[10], EMACRXCNTGUNI, RESERVED10[239],
EMACVLNINCREP, EMACVLANHASH, RESERVED11[93], EMACTIMSTCTRL, EMACSUBSECINC,
EMACTIMSEC, EMACTIMNANO, EMACTIMSECU, EMACTIMNANOU, EMACTIMADD,
EMACTARGSEC, EMACTARGNANO, EMACHWORDSEC, EMACTIMSTAT, EMACPPSCTRL,
RESERVED12[12], EMACPPS0INTVL, EMACPPS0WIDTH, RESERVED13[294],
EMACDMABUSMOD, EMACTXPOLLD, EMACRXPOLLD, EMACRXDLADDR, EMACTXDLADDR,
EMACDMARIS, EMACDMAOPMODE, EMACDMAIM, EMACMFBOC, EMACRXINTWDT,
RESERVED14[8], EMACHOSTXDESC, EMACHOSRXDESC, EMACHOSTXBA, EMACHOSRXBA,
RESERVED15[218], EMACPP, EMACPC, EMACCC, RESERVED16, EMACEPHYRIS,
EMACEPHYIM, EMACEPHYIMSC;
};
#undef EMAC
#define EMAC ((struct tm4c_emac *) (uintptr_t) 0x400EC000)
#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 struct mg_tcpip_if *s_ifp; // MIP interface
enum {
EPHY_ADDR = 0,
EPHYBMCR = 0,
EPHYBMSR = 1,
EPHYSTS = 16
}; // PHY constants
static inline void tm4cspin(volatile uint32_t count) {
while (count--) (void) 0;
}
static uint32_t emac_read_phy(uint8_t addr, uint8_t reg) {
EMAC->EMACMIIADDR &= (0xf << 2);
EMAC->EMACMIIADDR |= ((uint32_t) addr << 11) | ((uint32_t) reg << 6);
EMAC->EMACMIIADDR |= MG_BIT(0);
while (EMAC->EMACMIIADDR & MG_BIT(0)) tm4cspin(1);
return EMAC->EMACMIIDATA;
}
static void emac_write_phy(uint8_t addr, uint8_t reg, uint32_t val) {
EMAC->EMACMIIDATA = val;
EMAC->EMACMIIADDR &= (0xf << 2);
EMAC->EMACMIIADDR |=
((uint32_t) addr << 11) | ((uint32_t) reg << 6) | MG_BIT(1);
EMAC->EMACMIIADDR |= MG_BIT(0);
while (EMAC->EMACMIIADDR & MG_BIT(0)) tm4cspin(1);
}
static uint32_t get_sysclk(void) {
struct sysctl {
volatile uint32_t DONTCARE0[44], RSCLKCFG, DONTCARE1[43], PLLFREQ0,
PLLFREQ1;
} *sysctl = (struct sysctl *) 0x400FE000;
uint32_t clk = 0, piosc = 16000000 /* 16 MHz */, mosc = 25000000 /* 25MHz */;
if (sysctl->RSCLKCFG & (1 << 28)) { // USEPLL
uint32_t fin, vco, mdiv, n, q, psysdiv;
uint32_t pllsrc = (sysctl->RSCLKCFG & (0xf << 24)) >> 24;
if (pllsrc == 0) {
clk = piosc;
} else if (pllsrc == 3) {
clk = mosc;
} else {
MG_ERROR(("Unsupported clock source"));
}
q = (sysctl->PLLFREQ1 & (0x1f << 8)) >> 8;
n = (sysctl->PLLFREQ1 & (0x1f << 0)) >> 0;
fin = clk / ((q + 1) * (n + 1));
mdiv = (sysctl->PLLFREQ0 & (0x3ff << 0)) >>
0; // mint + (mfrac / 1024); MFRAC not supported
psysdiv = (sysctl->RSCLKCFG & (0x3f << 0)) >> 0;
vco = (uint32_t) ((uint64_t) fin * mdiv);
return vco / (psysdiv + 1);
}
uint32_t oscsrc = (sysctl->RSCLKCFG & (0xf << 20)) >> 20;
if (oscsrc == 0) {
clk = piosc;
} else if (oscsrc == 3) {
clk = mosc;
} else {
MG_ERROR(("Unsupported clock source"));
}
uint32_t osysdiv = (sysctl->RSCLKCFG & (0xf << 16)) >> 16;
return clk / (osysdiv + 1);
}
// Guess CR from SYSCLK. MDC clock is generated from SYSCLK (AHB); as per
// 802.3, it must not exceed 2.5MHz (also 20.4.2.6) As the AHB clock can be
// derived from the PIOSC (internal RC), and it can go above specs, the
// datasheets specify a range of frequencies and activate one of a series of
// dividers to keep the MDC clock safely below 2.5MHz. We guess a divider
// setting based on SYSCLK with a +5% drift. If the user uses a different clock
// from our defaults, needs to set the macros on top Valid for TM4C129x (20.7)
// (4.5% worst case drift)
// The PHY receives the main oscillator (MOSC) (20.3.1)
static int guess_mdc_cr(void) {
uint8_t crs[] = {2, 3, 0, 1}; // EMAC->MACMIIAR::CR values
uint8_t div[] = {16, 26, 42, 62}; // Respective HCLK dividers
uint32_t sysclk = get_sysclk(); // Guess system SYSCLK
int i, result = -1; // Invalid CR value
if (sysclk < 25000000) {
MG_ERROR(("SYSCLK too low"));
} else {
for (i = 0; i < 4; i++) {
if (sysclk / div[i] <= 2375000UL /* 2.5MHz - 5% */) {
result = crs[i];
break;
}
}
if (result < 0) MG_ERROR(("SYSCLK too high"));
}
MG_DEBUG(("SYSCLK: %u, CR: %d", sysclk, result));
return result;
}
static bool mg_tcpip_driver_tm4c_init(struct mg_tcpip_if *ifp) {
struct mg_tcpip_driver_tm4c_data *d =
(struct mg_tcpip_driver_tm4c_data *) ifp->driver_data;
int i;
s_ifp = ifp;
// Init RX descriptors
for (i = 0; i < ETH_DESC_CNT; i++) {
s_rxdesc[i][0] = MG_BIT(31); // Own
s_rxdesc[i][1] = sizeof(s_rxbuf[i]) | MG_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
// MG_DEBUG(("%d %p", i, s_rxdesc[i]));
}
// Init TX descriptors
for (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
}
EMAC->EMACDMABUSMOD |= MG_BIT(0); // Software reset
while ((EMAC->EMACDMABUSMOD & MG_BIT(0)) != 0)
tm4cspin(1); // Wait until done
// Set MDC clock divider. If user told us the value, use it. Otherwise, guess
int cr = (d == NULL || d->mdc_cr < 0) ? guess_mdc_cr() : d->mdc_cr;
EMAC->EMACMIIADDR = ((uint32_t) cr & 0xf) << 2;
// NOTE(cpq): we do not use extended descriptor bit 7, and do not use
// hardware checksum. Therefore, descriptor size is 4, not 8
// EMAC->EMACDMABUSMOD = MG_BIT(13) | MG_BIT(16) | MG_BIT(22) | MG_BIT(23) |
// MG_BIT(25);
EMAC->EMACIM = MG_BIT(3) | MG_BIT(9); // Mask timestamp & PMT IT
EMAC->EMACFLOWCTL = MG_BIT(7); // Disable zero-quanta pause
EMAC->EMACFRAMEFLTR = MG_BIT(10); // Perfect filtering
// EMAC->EMACPC defaults to internal PHY (EPHY) in MMI mode
emac_write_phy(EPHY_ADDR, EPHYBMCR, MG_BIT(15)); // Reset internal PHY (EPHY)
emac_write_phy(EPHY_ADDR, EPHYBMCR, MG_BIT(12)); // Set autonegotiation
EMAC->EMACRXDLADDR = (uint32_t) (uintptr_t) s_rxdesc; // RX descriptors
EMAC->EMACTXDLADDR = (uint32_t) (uintptr_t) s_txdesc; // TX descriptors
EMAC->EMACDMAIM = MG_BIT(6) | MG_BIT(16); // RIE, NIE
EMAC->EMACCFG =
MG_BIT(2) | MG_BIT(3) | MG_BIT(11) | MG_BIT(14); // RE, TE, Duplex, Fast
EMAC->EMACDMAOPMODE =
MG_BIT(1) | MG_BIT(13) | MG_BIT(21) | MG_BIT(25); // SR, ST, TSF, RSF
EMAC->EMACADDR0H = ((uint32_t) ifp->mac[5] << 8U) | ifp->mac[4];
EMAC->EMACADDR0L = (uint32_t) (ifp->mac[3] << 24) |
((uint32_t) ifp->mac[2] << 16) |
((uint32_t) ifp->mac[1] << 8) | ifp->mac[0];
return true;
}
static uint32_t s_txno;
static size_t mg_tcpip_driver_tm4c_tx(const void *buf, size_t len,
struct mg_tcpip_if *ifp) {
if (len > sizeof(s_txbuf[s_txno])) {
MG_ERROR(("Frame too big, %ld", (long) len));
len = 0; // fail
} else if ((s_txdesc[s_txno][0] & MG_BIT(31))) {
ifp->nerr++;
MG_ERROR(("No descriptors available"));
// printf("D0 %lx SR %lx\n", (long) s_txdesc[0][0], (long)
// EMAC->EMACDMARIS);
len = 0; // 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] =
MG_BIT(20) | MG_BIT(28) | MG_BIT(29) | MG_BIT(30); // Chain,FS,LS,IC
s_txdesc[s_txno][0] |= MG_BIT(31); // Set OWN bit - let DMA take over
if (++s_txno >= ETH_DESC_CNT) s_txno = 0;
}
EMAC->EMACDMARIS = MG_BIT(2) | MG_BIT(5); // Clear any prior TU/UNF
EMAC->EMACTXPOLLD = 0; // and resume
return len;
}
static void mg_tcpip_driver_tm4c_update_hash_table(struct mg_tcpip_if *ifp) {
// TODO(): read database, rebuild hash table
// add mDNS / DNS-SD multicast address
EMAC->EMACADDR1L = (uint32_t) mcast_addr[3] << 24 |
(uint32_t) mcast_addr[2] << 16 |
(uint32_t) mcast_addr[1] << 8 | (uint32_t) mcast_addr[0];
EMAC->EMACADDR1H = (uint32_t) mcast_addr[5] << 8 | (uint32_t) mcast_addr[4];
EMAC->EMACADDR1H |= MG_BIT(31); // AE
(void) ifp;
}
static bool mg_tcpip_driver_tm4c_poll(struct mg_tcpip_if *ifp, bool s1) {
if (ifp->update_mac_hash_table) {
mg_tcpip_driver_tm4c_update_hash_table(ifp);
ifp->update_mac_hash_table = false;
}
if (!s1) return false;
uint32_t bmsr = emac_read_phy(EPHY_ADDR, EPHYBMSR);
bool up = (bmsr & MG_BIT(2)) ? 1 : 0;
if ((ifp->state == MG_TCPIP_STATE_DOWN) && up) { // link state just went up
uint32_t sts = emac_read_phy(EPHY_ADDR, EPHYSTS);
// tmp = reg with flags set to the most likely situation: 100M full-duplex
// if(link is slow or half) set flags otherwise
// reg = tmp
uint32_t emaccfg =
EMAC->EMACCFG | MG_BIT(14) | MG_BIT(11); // 100M, Full-duplex
if (sts & MG_BIT(1)) emaccfg &= ~MG_BIT(14); // 10M
if ((sts & MG_BIT(2)) == 0) emaccfg &= ~MG_BIT(11); // Half-duplex
EMAC->EMACCFG = emaccfg; // IRQ handler does not fiddle with this register
MG_DEBUG(("Link is %uM %s-duplex", emaccfg & MG_BIT(14) ? 100 : 10,
emaccfg & MG_BIT(11) ? "full" : "half"));
}
return up;
}
void EMAC0_IRQHandler(void);
static uint32_t s_rxno;
void EMAC0_IRQHandler(void) {
int i;
if (EMAC->EMACDMARIS & MG_BIT(6)) { // Frame received, loop
EMAC->EMACDMARIS = MG_BIT(16) | MG_BIT(6); // Clear flag
for (i = 0; i < 10; i++) { // read as they arrive but not forever
if (s_rxdesc[s_rxno][0] & MG_BIT(31)) break; // exit when done
if (((s_rxdesc[s_rxno][0] & (MG_BIT(8) | MG_BIT(9))) ==
(MG_BIT(8) | MG_BIT(9))) &&
!(s_rxdesc[s_rxno][0] & MG_BIT(15))) { // skip partial/errored frames
uint32_t len = ((s_rxdesc[s_rxno][0] >> 16) & (MG_BIT(14) - 1));
// printf("%lx %lu %lx %.8lx\n", s_rxno, len, s_rxdesc[s_rxno][0],
// EMAC->EMACDMARIS);
mg_tcpip_qwrite(s_rxbuf[s_rxno], len > 4 ? len - 4 : len, s_ifp);
}
s_rxdesc[s_rxno][0] = MG_BIT(31);
if (++s_rxno >= ETH_DESC_CNT) s_rxno = 0;
}
}
EMAC->EMACDMARIS = MG_BIT(7); // Clear possible RU while processing
EMAC->EMACRXPOLLD = 0; // and resume RX
}
struct mg_tcpip_driver mg_tcpip_driver_tm4c = {mg_tcpip_driver_tm4c_init,
mg_tcpip_driver_tm4c_tx, NULL,
mg_tcpip_driver_tm4c_poll};
#endif