ref: 7628681f83b663609eace87a50f8fbf68c31f40b
dir: /sys/src/9/imx8/uartimx.c/
#include "u.h"
#include "../port/lib.h"
#include "../port/error.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
enum {
URXD = 0x00/4, /* UART Receiver Register */
RX_CHARRDY = 1<<15,
RX_ERR = 1<<14,
RX_OVRRUN = 1<<13,
RX_FRMERR = 1<<12,
RX_BRK = 1<<11,
RX_PRERR = 1<<10,
RX_DATA = 0xFF,
UTXD = 0x40/4, /* UART Transmitter Register */
TX_DATA = 0xFF,
UCR1 = 0x80/4, /* UART Control Register 1 */
CR1_ADEN = 1<<15, /* Automatic Baud Rate Detection Interrupt Enable */
CR1_ADNR = 1<<14, /* Automatic Detection of Baud Rate */
CR1_TRDYEN = 1<<13, /* Transmitter Ready Interrupt Enable */
CR1_IDEN = 1<<12, /* Idle Condition Detected Interrupt Enable */
CR1_ICD_SHIFT = 10, /* Idle Condition Detect Mask */
CR1_ICD_MASK = 3<<CR1_ICD_SHIFT,
CR1_RRDYEN = 1<<9, /* Receiver Ready Interrupt Enable */
CR1_RXDMAEN = 1<<8, /* Receive Ready DMA Enable */
CR1_IREN = 1<<7, /* Infrared Interface Enable */
CR1_TXMPTYEN = 1<<6, /* Transmitter Empty Interrupt Enable */
CR1_RTSDEN = 1<<5, /* RTS Delta Interrupt Enable */
CR1_SNDBRK = 1<<4, /* Send BREAK */
CR1_TXDMAEN = 1<<3, /* Transmitter Ready DMA Enable */
CR1_ATDMAEN = 1<<2, /* Aging DMA Timer Enable */
CR1_DOZE = 1<<1, /* DOZE */
CR1_UARTEN = 1<<0, /* Uart Enable */
UCR2 = 0x84/4, /* UART Control Register 2 */
CR2_ESCI = 1<<15, /* Escape Sequence Interrupt Enable */
CR2_IRTS = 1<<14, /* Ignore RTS Pin */
CR2_CTSC = 1<<13, /* CTS Pin Control */
CR2_CTS = 1<<12, /* Clear to Send */
CR2_ESCEN = 1<<11, /* Escape Enable */
CR2_RTEC_RAISING= 0<<9,
CR2_RTEC_FALLING= 1<<9,
CR2_RTEC_ANY = 2<<9,
CR2_RTEC_MASK = 3<<9,
CR2_PREN = 1<<8, /* Parity Enable */
CR2_PREVEN = 0<<7, /* Parity Even */
CR2_PRODD = 1<<7, /* Parity Odd */
CR2_STPB = 1<<6, /* Stop */
CR2_WS8 = 1<<5, /* Word Size */
CR2_WS7 = 0<<5,
CR2_RTSEN = 1<<4, /* Request to Send Interrupt Enable */
CR2_ATEN = 1<<3, /* Aging Timer Enable */
CR2_TXEN = 1<<2, /* Transmitter Enable */
CR2_RXEN = 1<<1, /* Receiver Enable */
CR2_SRST = 1<<0, /* Software Reset */
UCR3 = 0x88/4, /* UART Control Register 3 */
CR3_PARERREN = 1<<12, /* Parity Error Interrupt Enable */
CR3_FRAERREN = 1<<11, /* Frame Error Interrupt Enable */
CR3_ADNIMP = 1<<7, /* Autobaud Detection Not Improved */
CR3_RXDSEN = 1<<6, /* Receive Status Interrupt Enable */
CR3_AIRINTEN = 1<<5, /* Asynchronous IR WAKE Interrupt Enable */
CR3_AWAKEN = 1<<4, /* Asynchronous WAKE Interrupt Enable */
CR3_RXDMUXSEL = 1<<2, /* RXD Muxed Input Selected */
CR3_INVT = 1<<1, /* Invert TXD output in RS-232/RS-485 mode */
CR3_ACIEN = 1<<0, /* Autobaud Counter Interrupt Enable */
UCR4 = 0x8C/4, /* UART Control Register 4 */
CR4_CTSTL_SHIFT = 10, /* CTS Trigger Level */
CR4_CTSTL_MASK = 0x3F<<CR4_CTSTL_SHIFT,
CR4_INVR = 1<<9, /* Invert RXD Input in RS-232/RS-485 Mode */
CR4_ENIRI = 1<<8, /* Serial Infrared Interrupt Enable */
CR4_WKEN = 1<<7, /* WAKE Interrupt Enable */
CR4_IDDMAEN = 1<<6, /* DMA IDLE Condition Detected Interrupt Enable */
CR4_IRSC = 1<<5, /* IR Special Case */
CR4_LPBYP = 1<<4, /* Low Power Bypass */
CR4_TCEN = 1<<3, /* Transmit Complete Interrupt Enable */
CR4_BKEN = 1<<2, /* BREAK Condition Detected Interrupt Enable */
CR4_OREN = 1<<1, /* Receiver Overrun Interrupt Enable */
CR4_DREN = 1<<0, /* Receive Data Interrupt Enable */
UFCR = 0x90/4, /* UART FIFO Control Register */
FCR_TXTL_SHIFT = 10, /* Transmitter Trigger Level */
FCR_TXTL_MASK = 0x3F<<FCR_TXTL_SHIFT,
FCR_RFDIV_SHIFT = 7, /* Reference Frequency Divider */
FCR_RFDIV_MASK = 0x7<<FCR_RFDIV_SHIFT,
FCR_DCE = 0<<6, /* DCE/DTE mode select */
FCR_DTE = 1<<6,
FCR_RXTL_SHIFT = 0, /* Receive Trigger Level */
FCR_RXTL_MASK = 0x3F<<FCR_RXTL_SHIFT,
USR1 = 0x94/4, /* UART Status Register 1 */
SR1_PARITYERR = 1<<15, /* Parity Error Interrupt Flag */
SR1_RTSS = 1<<14, /* RTS_B Pin Status */
SR1_TRDY = 1<<13, /* Transmitter Ready Interrupt / DMA Flag */
SR1_RTSD = 1<<12, /* RTS Delta */
SR1_ESCF = 1<<11, /* Escape Sequence Interrupt Flag */
SR1_FRAMEERR = 1<<10, /* Frame Error Interrupt Flag */
SR1_RRDY = 1<<9, /* Receiver Ready Interrupt / DMA Flag */
SR1_AGTIM = 1<<8, /* Aging Timer Interrupt Flag */
SR1_DTRD = 1<<7,
SR1_RXDS = 1<<6, /* Receiver IDLE Interrupt Flag */
SR1_AIRINT = 1<<5, /* Asynchronous IR WAKE Interrupt Flag */
SR1_AWAKE = 1<<4, /* Asynchronous WAKE Interrupt Flag */
SR1_SAD = 1<<3, /* RS-485 Slave Address Detected Interrupt Flag */
USR2 = 0x98/4, /* UART Status Register 2 */
SR2_ADET = 1<<15, /* Automatic Baud Rate Detected Complete */
SR2_TXFE = 1<<14, /* Transmit Buffer FIFO Empty */
SR2_DTRF = 1<<13,
SR2_IDLE = 1<<12, /* Idle Condition */
SR2_ACST = 1<<11, /* Autobaud Counter Stopped */
SR2_RIDELT = 1<<10,
SR2_RIIN = 1<<9,
SR2_IRINT = 1<<8, /* Serial Infrared Interrupt Flag */
SR2_WAKE = 1<<7, /* Wake */
SR2_DCDDELT = 1<<6,
SR2_DCDIN = 1<<5,
SR2_RTSF = 1<<4, /* RTS Edge Triggered Interrupt Flag */
SR2_TXDC = 1<<3, /* Transmitter Complete */
SR2_BRCD = 1<<2, /* BREAK Condition Detected */
SR2_ORE = 1<<1, /* Overrun Error */
SR2_RDR = 1<<0, /* Receive Data Ready */
UESC = 0x9C/4, /* UART Escape Character Register */
UTIM = 0xA0/4, /* UART Escape Timer Register */
UBIR = 0xA4/4, /* UART BRM Incremental Modulator Register */
UBMR = 0xA8/4, /* UART BRM Modulator Register */
UBRC = 0xAC/4, /* UART Baud Rate Count Register */
ONEMS = 0xB0/4, /* UART One-Millisecond Register */
UTS = 0xB5/4, /* UART Test Register */
UMCR = 0xB8/4, /* UART RS-485 Mode Control Register */
};
extern PhysUart imxphysuart;
static Uart uart1 = {
.regs = (u32int*)(VIRTIO + 0x860000ULL),
.name = "uart1",
.baud = 115200,
.freq = 25*Mhz,
.phys = &imxphysuart,
};
static Uart*
pnp(void)
{
return &uart1;
}
static void
kick(Uart *u)
{
u32int *regs = (u32int*)u->regs;
while(u->op < u->oe || uartstageoutput(u)){
if((regs[USR1] & SR1_TRDY) == 0){
regs[UCR1] |= CR1_TRDYEN;
return;
}
regs[UTXD] = *(u->op++) & TX_DATA;
}
regs[UCR1] &= ~CR1_TRDYEN;
}
static void
config(Uart *u)
{
u32int cr2, *regs = u->regs;
/* enable uart */
regs[UCR1] = CR1_UARTEN;
cr2 = CR2_SRST | CR2_IRTS | CR2_RXEN | CR2_TXEN;
switch(u->parity){
case 'e': cr2 |= CR2_PREN | CR2_PREVEN; break;
case 'o': cr2 |= CR2_PREN | CR2_PRODD; break;
}
cr2 |= u->bits == 7 ? CR2_WS7 : CR2_WS8;
if(u->stop == 2) cr2 |= CR2_STPB;
regs[UCR2] = cr2;
regs[UCR3] = 0x7<<8 | CR3_RXDMUXSEL;
regs[UCR4] = 31<<CR4_CTSTL_SHIFT;
/* baud = clock / (16 * (ubmr+1)/(ubir+1)) */
regs[UFCR] = (6 - 1)<<FCR_RFDIV_SHIFT | 16<<FCR_TXTL_SHIFT | 1<<FCR_RXTL_SHIFT;
regs[UBIR] = ((16*u->baud) / 1600)-1;
regs[UBMR] = (u->freq / 1600)-1;
regs[UCR1] = CR1_UARTEN | CR1_RRDYEN;
}
static int
bits(Uart *u, int n)
{
switch(n){
case 8:
break;
case 7:
break;
default:
return -1;
}
u->bits = n;
config(u);
return 0;
}
static int
stop(Uart *u, int n)
{
switch(n){
case 1:
break;
case 2:
break;
default:
return -1;
}
u->stop = n;
config(u);
return 0;
}
static int
parity(Uart *u, int n)
{
switch(n){
case 'n':
break;
case 'e':
break;
case 'o':
break;
default:
return -1;
}
u->parity = n;
config(u);
return 0;
}
static int
baud(Uart *u, int n)
{
if(u->freq == 0 || n <= 0)
return -1;
u->baud = n;
config(u);
return 0;
}
static void
rts(Uart*, int)
{
}
static void
dobreak(Uart*, int)
{
}
static long
status(Uart *uart, void *buf, long n, long offset)
{
char *p;
p = malloc(READSTR);
if(p == nil)
error(Enomem);
snprint(p, READSTR,
"b%d\n"
"dev(%d) type(%d) framing(%d) overruns(%d) "
"berr(%d) serr(%d)\n",
uart->baud,
uart->dev,
uart->type,
uart->ferr,
uart->oerr,
uart->berr,
uart->serr
);
n = readstr(offset, buf, n, p);
free(p);
return n;
}
static void
interrupt(Ureg*, void *arg)
{
Uart *uart = arg;
u32int v, *regs = (u32int*)uart->regs;
while((v = regs[URXD]) & RX_CHARRDY)
uartrecv(uart, v & RX_DATA);
uartkick(uart);
}
static void
clkenable(Uart *u, int on)
{
char clk[32];
snprint(clk, sizeof(clk), "%s.ipg_perclk", u->name);
if(on) setclkrate(clk, "osc_25m_ref_clk", u->freq);
setclkgate(clk, on);
}
static void
disable(Uart *u)
{
u32int *regs = u->regs;
if(u->console)
return; /* avoid glitch */
regs[UCR1] = 0;
clkenable(u, 0);
}
static void
enable(Uart *u, int ie)
{
disable(u);
clkenable(u, 1);
if(ie) intrenable(IRQuart1, interrupt, u, BUSUNKNOWN, u->name);
config(u);
}
static void
donothing(Uart*, int)
{
}
static void
putc(Uart *u, int c)
{
u32int *regs = u->regs;
while((regs[USR1] & SR1_TRDY) == 0)
;
regs[UTXD] = c & TX_DATA;
}
static int
getc(Uart *u)
{
u32int c, *regs = (u32int*)u->regs;
do
c = regs[URXD];
while((c & RX_CHARRDY) == 0);
return c & RX_DATA;
}
void
uartconsinit(void)
{
consuart = &uart1;
consuart->console = 1;
uartctl(consuart, "l8 pn s1");
}
PhysUart imxphysuart = {
.name = "imx",
.pnp = pnp,
.enable = enable,
.disable = disable,
.kick = kick,
.dobreak = dobreak,
.baud = baud,
.bits = bits,
.stop = stop,
.parity = parity,
.modemctl = donothing,
.rts = rts,
.dtr = donothing,
.status = status,
.fifo = donothing,
.getc = getc,
.putc = putc,
};