u-boot/arch/powerpc/cpu/mpc85xx/serial_scc.c

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// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2003 Motorola Inc.
* Xianghua Xiao (X.Xiao@motorola.com)
* Modified based on 8260 for 8560.
*
* (C) Copyright 2000
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* Hacked for MPC8260 by Murray.Jensen@cmst.csiro.au, 19-Oct-00.
*/
/*
* Minimal serial functions needed to use one of the SCC ports
* as serial console interface.
*/
#include <common.h>
#include <asm/cpm_85xx.h>
#include <serial.h>
#include <asm/global_data.h>
#include <linux/compiler.h>
DECLARE_GLOBAL_DATA_PTR;
#if defined(CONFIG_CONS_ON_SCC)
#if CONFIG_CONS_INDEX == 1 /* Console on SCC1 */
#define SCC_INDEX 0
#define PROFF_SCC PROFF_SCC1
#define CMXSCR_MASK (CMXSCR_GR1|CMXSCR_SC1|\
CMXSCR_RS1CS_MSK|CMXSCR_TS1CS_MSK)
#define CMXSCR_VALUE (CMXSCR_RS1CS_BRG1|CMXSCR_TS1CS_BRG1)
#define CPM_CR_SCC_PAGE CPM_CR_SCC1_PAGE
#define CPM_CR_SCC_SBLOCK CPM_CR_SCC1_SBLOCK
#elif CONFIG_CONS_INDEX == 2 /* Console on SCC2 */
#define SCC_INDEX 1
#define PROFF_SCC PROFF_SCC2
#define CMXSCR_MASK (CMXSCR_GR2|CMXSCR_SC2|\
CMXSCR_RS2CS_MSK|CMXSCR_TS2CS_MSK)
#define CMXSCR_VALUE (CMXSCR_RS2CS_BRG2|CMXSCR_TS2CS_BRG2)
#define CPM_CR_SCC_PAGE CPM_CR_SCC2_PAGE
#define CPM_CR_SCC_SBLOCK CPM_CR_SCC2_SBLOCK
#elif CONFIG_CONS_INDEX == 3 /* Console on SCC3 */
#define SCC_INDEX 2
#define PROFF_SCC PROFF_SCC3
#define CMXSCR_MASK (CMXSCR_GR3|CMXSCR_SC3|\
CMXSCR_RS3CS_MSK|CMXSCR_TS3CS_MSK)
#define CMXSCR_VALUE (CMXSCR_RS3CS_BRG3|CMXSCR_TS3CS_BRG3)
#define CPM_CR_SCC_PAGE CPM_CR_SCC3_PAGE
#define CPM_CR_SCC_SBLOCK CPM_CR_SCC3_SBLOCK
#elif CONFIG_CONS_INDEX == 4 /* Console on SCC4 */
#define SCC_INDEX 3
#define PROFF_SCC PROFF_SCC4
#define CMXSCR_MASK (CMXSCR_GR4|CMXSCR_SC4|\
CMXSCR_RS4CS_MSK|CMXSCR_TS4CS_MSK)
#define CMXSCR_VALUE (CMXSCR_RS4CS_BRG4|CMXSCR_TS4CS_BRG4)
#define CPM_CR_SCC_PAGE CPM_CR_SCC4_PAGE
#define CPM_CR_SCC_SBLOCK CPM_CR_SCC4_SBLOCK
#else
#error "console not correctly defined"
#endif
static int mpc85xx_serial_init(void)
{
volatile ccsr_cpm_t *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
volatile ccsr_cpm_scc_t *sp;
volatile scc_uart_t *up;
volatile cbd_t *tbdf, *rbdf;
volatile ccsr_cpm_cp_t *cp = &(cpm->im_cpm_cp);
uint dpaddr;
/* initialize pointers to SCC */
sp = (ccsr_cpm_scc_t *) &(cpm->im_cpm_scc[SCC_INDEX]);
up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
/* Disable transmitter/receiver.
*/
sp->gsmrl &= ~(SCC_GSMRL_ENR | SCC_GSMRL_ENT);
/* put the SCC channel into NMSI (non multiplexd serial interface)
* mode and wire the selected SCC Tx and Rx clocks to BRGx (15-15).
*/
cpm->im_cpm_mux.cmxscr = \
(cpm->im_cpm_mux.cmxscr&~CMXSCR_MASK)|CMXSCR_VALUE;
/* Set up the baud rate generator.
*/
serial_setbrg ();
/* Allocate space for two buffer descriptors in the DP ram.
* damm: allocating space after the two buffers for rx/tx data
*/
dpaddr = m8560_cpm_dpalloc((2 * sizeof (cbd_t)) + 2, 16);
/* Set the physical address of the host memory buffers in
* the buffer descriptors.
*/
rbdf = (cbd_t *)&(cpm->im_dprambase[dpaddr]);
rbdf->cbd_bufaddr = (uint) (rbdf+2);
rbdf->cbd_sc = BD_SC_EMPTY | BD_SC_WRAP;
tbdf = rbdf + 1;
tbdf->cbd_bufaddr = ((uint) (rbdf+2)) + 1;
tbdf->cbd_sc = BD_SC_WRAP;
/* Set up the uart parameters in the parameter ram.
*/
up->scc_genscc.scc_rbase = dpaddr;
up->scc_genscc.scc_tbase = dpaddr+sizeof(cbd_t);
up->scc_genscc.scc_rfcr = CPMFCR_EB;
up->scc_genscc.scc_tfcr = CPMFCR_EB;
up->scc_genscc.scc_mrblr = 1;
up->scc_maxidl = 0;
up->scc_brkcr = 1;
up->scc_parec = 0;
up->scc_frmec = 0;
up->scc_nosec = 0;
up->scc_brkec = 0;
up->scc_uaddr1 = 0;
up->scc_uaddr2 = 0;
up->scc_toseq = 0;
up->scc_char1 = up->scc_char2 = up->scc_char3 = up->scc_char4 = 0x8000;
up->scc_char5 = up->scc_char6 = up->scc_char7 = up->scc_char8 = 0x8000;
up->scc_rccm = 0xc0ff;
/* Mask all interrupts and remove anything pending.
*/
sp->sccm = 0;
sp->scce = 0xffff;
/* Set 8 bit FIFO, 16 bit oversampling and UART mode.
*/
sp->gsmrh = SCC_GSMRH_RFW; /* 8 bit FIFO */
sp->gsmrl = \
SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16 | SCC_GSMRL_MODE_UART;
/* Set CTS no flow control, 1 stop bit, 8 bit character length,
* normal async UART mode, no parity
*/
sp->psmr = SCU_PSMR_CL;
/* execute the "Init Rx and Tx params" CP command.
*/
while (cp->cpcr & CPM_CR_FLG) /* wait if cp is busy */
;
cp->cpcr = mk_cr_cmd(CPM_CR_SCC_PAGE, CPM_CR_SCC_SBLOCK,
0, CPM_CR_INIT_TRX) | CPM_CR_FLG;
while (cp->cpcr & CPM_CR_FLG) /* wait if cp is busy */
;
/* Enable transmitter/receiver.
*/
sp->gsmrl |= SCC_GSMRL_ENR | SCC_GSMRL_ENT;
return (0);
}
static void mpc85xx_serial_setbrg(void)
{
#if defined(CONFIG_CONS_USE_EXTC)
m8560_cpm_extcbrg(SCC_INDEX, gd->baudrate,
CONFIG_CONS_EXTC_RATE, CONFIG_CONS_EXTC_PINSEL);
#else
m8560_cpm_setbrg(SCC_INDEX, gd->baudrate);
#endif
}
static void mpc85xx_serial_putc(const char c)
{
volatile scc_uart_t *up;
volatile cbd_t *tbdf;
volatile ccsr_cpm_t *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
if (c == '\n')
serial_putc ('\r');
up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
tbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_tbase]);
/* Wait for last character to go.
*/
while (tbdf->cbd_sc & BD_SC_READY)
;
/* Load the character into the transmit buffer.
*/
*(volatile char *)tbdf->cbd_bufaddr = c;
tbdf->cbd_datlen = 1;
tbdf->cbd_sc |= BD_SC_READY;
}
static int mpc85xx_serial_getc(void)
{
volatile cbd_t *rbdf;
volatile scc_uart_t *up;
volatile ccsr_cpm_t *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
unsigned char c;
up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
rbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_rbase]);
/* Wait for character to show up.
*/
while (rbdf->cbd_sc & BD_SC_EMPTY)
;
/* Grab the char and clear the buffer again.
*/
c = *(volatile unsigned char *)rbdf->cbd_bufaddr;
rbdf->cbd_sc |= BD_SC_EMPTY;
return (c);
}
static int mpc85xx_serial_tstc(void)
{
volatile cbd_t *rbdf;
volatile scc_uart_t *up;
volatile ccsr_cpm_t *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
rbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_rbase]);
return ((rbdf->cbd_sc & BD_SC_EMPTY) == 0);
}
static struct serial_device mpc85xx_serial_drv = {
.name = "mpc85xx_serial",
.start = mpc85xx_serial_init,
.stop = NULL,
.setbrg = mpc85xx_serial_setbrg,
.putc = mpc85xx_serial_putc,
.puts = default_serial_puts,
.getc = mpc85xx_serial_getc,
.tstc = mpc85xx_serial_tstc,
};
void mpc85xx_serial_initialize(void)
{
serial_register(&mpc85xx_serial_drv);
}
__weak struct serial_device *default_serial_console(void)
{
return &mpc85xx_serial_drv;
}
#endif /* CONFIG_CONS_ON_SCC */