linux-stable-rt/arch/ppc/boot/simple/m8xx_tty.c

290 lines
6.7 KiB
C

/* Minimal serial functions needed to send messages out the serial
* port on the MBX console.
*
* The MBX uses SMC1 for the serial port. We reset the port and use
* only the first BD that EPPC-Bug set up as a character FIFO.
*
* Later versions (at least 1.4, maybe earlier) of the MBX EPPC-Bug
* use COM1 instead of SMC1 as the console port. This kinda sucks
* for the rest of the kernel, so here we force the use of SMC1 again.
*/
#include <linux/types.h>
#include <asm/uaccess.h>
#include <asm/mpc8xx.h>
#include <asm/commproc.h>
#ifdef CONFIG_MBX
#define MBX_CSR1 ((volatile u_char *)0xfa100000)
#define CSR1_COMEN (u_char)0x02
#endif
#ifdef TQM_SMC2_CONSOLE
#define PROFF_CONS PROFF_SMC2
#define CPM_CR_CH_CONS CPM_CR_CH_SMC2
#define SMC_INDEX 1
static volatile iop8xx_t *iopp = (iop8xx_t *)&(((immap_t *)IMAP_ADDR)->im_ioport);
#else
#define PROFF_CONS PROFF_SMC1
#define CPM_CR_CH_CONS CPM_CR_CH_SMC1
#define SMC_INDEX 0
#endif
static cpm8xx_t *cpmp = (cpm8xx_t *)&(((immap_t *)IMAP_ADDR)->im_cpm);
unsigned long
serial_init(int ignored, bd_t *bd)
{
volatile smc_t *sp;
volatile smc_uart_t *up;
volatile cbd_t *tbdf, *rbdf;
volatile cpm8xx_t *cp;
uint dpaddr, memaddr;
#ifndef CONFIG_MBX
uint ui;
#endif
cp = cpmp;
sp = (smc_t*)&(cp->cp_smc[SMC_INDEX]);
up = (smc_uart_t *)&cp->cp_dparam[PROFF_CONS];
/* Disable transmitter/receiver.
*/
sp->smc_smcmr &= ~(SMCMR_REN | SMCMR_TEN);
#ifdef CONFIG_FADS
/* Enable SMC1/2 transceivers.
*/
*((volatile uint *)BCSR1) &= ~(BCSR1_RS232EN_1|BCSR1_RS232EN_2);
#endif
#ifndef CONFIG_MBX
{
/* Initialize SMCx and use it for the console port.
*/
/* Enable SDMA.
*/
((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sdcr = 1;
#ifdef TQM_SMC2_CONSOLE
/* Use Port A for SMC2 instead of other functions.
*/
iopp->iop_papar |= 0x00c0;
iopp->iop_padir &= ~0x00c0;
iopp->iop_paodr &= ~0x00c0;
#else
/* Use Port B for SMCs instead of other functions.
*/
cp->cp_pbpar |= 0x00000cc0;
cp->cp_pbdir &= ~0x00000cc0;
cp->cp_pbodr &= ~0x00000cc0;
#endif
/* Allocate space for two buffer descriptors in the DP ram.
* For now, this address seems OK, but it may have to
* change with newer versions of the firmware.
*/
dpaddr = 0x0800;
/* Grab a few bytes from the top of memory for SMC FIFOs.
*/
memaddr = (bd->bi_memsize - 32) & ~15;
/* Set the physical address of the host memory buffers in
* the buffer descriptors.
*/
rbdf = (cbd_t *)&cp->cp_dpmem[dpaddr];
rbdf->cbd_bufaddr = memaddr;
rbdf->cbd_sc = 0;
tbdf = rbdf + 1;
tbdf->cbd_bufaddr = memaddr+4;
tbdf->cbd_sc = 0;
/* Set up the uart parameters in the parameter ram.
*/
up->smc_rbase = dpaddr;
up->smc_tbase = dpaddr+sizeof(cbd_t);
up->smc_rfcr = SMC_EB;
up->smc_tfcr = SMC_EB;
/* Set UART mode, 8 bit, no parity, one stop.
* Enable receive and transmit.
*/
sp->smc_smcmr = smcr_mk_clen(9) | SMCMR_SM_UART;
/* Mask all interrupts and remove anything pending.
*/
sp->smc_smcm = 0;
sp->smc_smce = 0xff;
/* Set up the baud rate generator.
* See 8xx_io/commproc.c for details.
* This wires BRG1 to SMC1 and BRG2 to SMC2;
*/
cp->cp_simode = 0x10000000;
ui = bd->bi_intfreq / 16 / bd->bi_baudrate;
#ifdef TQM_SMC2_CONSOLE
cp->cp_brgc2 =
#else
cp->cp_brgc1 =
#endif
((ui - 1) < 4096)
? (((ui - 1) << 1) | CPM_BRG_EN)
: ((((ui / 16) - 1) << 1) | CPM_BRG_EN | CPM_BRG_DIV16);
#else /* CONFIG_MBX */
if (*MBX_CSR1 & CSR1_COMEN) {
/* COM1 is enabled. Initialize SMC1 and use it for
* the console port.
*/
/* Enable SDMA.
*/
((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sdcr = 1;
/* Use Port B for SMCs instead of other functions.
*/
cp->cp_pbpar |= 0x00000cc0;
cp->cp_pbdir &= ~0x00000cc0;
cp->cp_pbodr &= ~0x00000cc0;
/* Allocate space for two buffer descriptors in the DP ram.
* For now, this address seems OK, but it may have to
* change with newer versions of the firmware.
*/
dpaddr = 0x0800;
/* Grab a few bytes from the top of memory. EPPC-Bug isn't
* running any more, so we can do this.
*/
memaddr = (bd->bi_memsize - 32) & ~15;
/* Set the physical address of the host memory buffers in
* the buffer descriptors.
*/
rbdf = (cbd_t *)&cp->cp_dpmem[dpaddr];
rbdf->cbd_bufaddr = memaddr;
rbdf->cbd_sc = 0;
tbdf = rbdf + 1;
tbdf->cbd_bufaddr = memaddr+4;
tbdf->cbd_sc = 0;
/* Set up the uart parameters in the parameter ram.
*/
up->smc_rbase = dpaddr;
up->smc_tbase = dpaddr+sizeof(cbd_t);
up->smc_rfcr = SMC_EB;
up->smc_tfcr = SMC_EB;
/* Set UART mode, 8 bit, no parity, one stop.
* Enable receive and transmit.
*/
sp->smc_smcmr = smcr_mk_clen(9) | SMCMR_SM_UART;
/* Mask all interrupts and remove anything pending.
*/
sp->smc_smcm = 0;
sp->smc_smce = 0xff;
/* Set up the baud rate generator.
* See 8xx_io/commproc.c for details.
*/
cp->cp_simode = 0x10000000;
cp->cp_brgc1 =
(((bd->bi_intfreq/16) / 9600) << 1) | CPM_BRG_EN;
/* Enable SMC1 for console output.
*/
*MBX_CSR1 &= ~CSR1_COMEN;
}
else {
#endif /* ndef CONFIG_MBX */
/* SMCx is used as console port.
*/
tbdf = (cbd_t *)&cp->cp_dpmem[up->smc_tbase];
rbdf = (cbd_t *)&cp->cp_dpmem[up->smc_rbase];
/* Issue a stop transmit, and wait for it.
*/
cp->cp_cpcr = mk_cr_cmd(CPM_CR_CH_CONS,
CPM_CR_STOP_TX) | CPM_CR_FLG;
while (cp->cp_cpcr & CPM_CR_FLG);
}
/* Make the first buffer the only buffer.
*/
tbdf->cbd_sc |= BD_SC_WRAP;
rbdf->cbd_sc |= BD_SC_EMPTY | BD_SC_WRAP;
/* Single character receive.
*/
up->smc_mrblr = 1;
up->smc_maxidl = 0;
/* Initialize Tx/Rx parameters.
*/
cp->cp_cpcr = mk_cr_cmd(CPM_CR_CH_CONS, CPM_CR_INIT_TRX) | CPM_CR_FLG;
while (cp->cp_cpcr & CPM_CR_FLG);
/* Enable transmitter/receiver.
*/
sp->smc_smcmr |= SMCMR_REN | SMCMR_TEN;
/* This is ignored.
*/
return 0;
}
void
serial_putc(void *ignored, const char c)
{
volatile cbd_t *tbdf;
volatile char *buf;
volatile smc_uart_t *up;
up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_CONS];
tbdf = (cbd_t *)&cpmp->cp_dpmem[up->smc_tbase];
/* Wait for last character to go.
*/
buf = (char *)tbdf->cbd_bufaddr;
while (tbdf->cbd_sc & BD_SC_READY);
*buf = c;
tbdf->cbd_datlen = 1;
tbdf->cbd_sc |= BD_SC_READY;
}
char
serial_getc(void *ignored)
{
volatile cbd_t *rbdf;
volatile char *buf;
volatile smc_uart_t *up;
char c;
up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_CONS];
rbdf = (cbd_t *)&cpmp->cp_dpmem[up->smc_rbase];
/* Wait for character to show up.
*/
buf = (char *)rbdf->cbd_bufaddr;
while (rbdf->cbd_sc & BD_SC_EMPTY);
c = *buf;
rbdf->cbd_sc |= BD_SC_EMPTY;
return(c);
}
int
serial_tstc(void *ignored)
{
volatile cbd_t *rbdf;
volatile smc_uart_t *up;
up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_CONS];
rbdf = (cbd_t *)&cpmp->cp_dpmem[up->smc_rbase];
return(!(rbdf->cbd_sc & BD_SC_EMPTY));
}