1138bbe05e
U-Boot serial code already handles -EAGAIN value from getc and putc callbacks. So change drivers code to return -EAGAIN when HW is busy instead of doing its own busy loop and waiting until HW is ready. Signed-off-by: Pali Rohár <pali@kernel.org>
254 lines
6.5 KiB
C
254 lines
6.5 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* (C) Copyright 2000
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* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
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*/
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#include <common.h>
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#include <command.h>
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#include <dm.h>
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#include <serial.h>
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#include <watchdog.h>
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#include <asm/cpm_8xx.h>
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#include <asm/global_data.h>
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#include <linux/compiler.h>
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DECLARE_GLOBAL_DATA_PTR;
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#if defined(CONFIG_8xx_CONS_SMC1) /* Console on SMC1 */
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#define SMC_INDEX 0
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#define PROFF_SMC PROFF_SMC1
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#define CPM_CR_CH_SMC CPM_CR_CH_SMC1
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#define IOPINS 0xc0
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#elif defined(CONFIG_8xx_CONS_SMC2) /* Console on SMC2 */
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#define SMC_INDEX 1
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#define PROFF_SMC PROFF_SMC2
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#define CPM_CR_CH_SMC CPM_CR_CH_SMC2
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#define IOPINS 0xc00
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#endif /* CONFIG_8xx_CONS_SMCx */
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struct serialbuffer {
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cbd_t rxbd; /* Rx BD */
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cbd_t txbd; /* Tx BD */
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uint rxindex; /* index for next character to read */
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uchar rxbuf[CONFIG_SYS_SMC_RXBUFLEN];/* rx buffers */
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uchar txbuf; /* tx buffers */
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};
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static void serial_setdivisor(cpm8xx_t __iomem *cp, int baudrate)
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{
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int divisor = (gd->cpu_clk + 8 * baudrate) / 16 / baudrate;
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if (divisor / 16 > 0x1000) {
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/* bad divisor, assume 50MHz clock and 9600 baud */
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divisor = (50 * 1000 * 1000 + 8 * 9600) / 16 / 9600;
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}
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divisor /= CONFIG_SYS_BRGCLK_PRESCALE;
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if (divisor <= 0x1000)
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out_be32(&cp->cp_brgc1, ((divisor - 1) << 1) | CPM_BRG_EN);
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else
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out_be32(&cp->cp_brgc1, ((divisor / 16 - 1) << 1) | CPM_BRG_EN |
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CPM_BRG_DIV16);
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}
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/*
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* Minimal serial functions needed to use one of the SMC ports
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* as serial console interface.
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*/
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static int serial_mpc8xx_setbrg(struct udevice *dev, int baudrate)
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{
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immap_t __iomem *im = (immap_t __iomem *)CONFIG_SYS_IMMR;
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cpm8xx_t __iomem *cp = &(im->im_cpm);
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/* Set up the baud rate generator.
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* See 8xx_io/commproc.c for details.
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*
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* Wire BRG1 to SMCx
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*/
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out_be32(&cp->cp_simode, 0);
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serial_setdivisor(cp, baudrate);
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return 0;
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}
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static int serial_mpc8xx_probe(struct udevice *dev)
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{
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immap_t __iomem *im = (immap_t __iomem *)CONFIG_SYS_IMMR;
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smc_t __iomem *sp;
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smc_uart_t __iomem *up;
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cpm8xx_t __iomem *cp = &(im->im_cpm);
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struct serialbuffer __iomem *rtx;
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/* initialize pointers to SMC */
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sp = cp->cp_smc + SMC_INDEX;
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up = (smc_uart_t __iomem *)&cp->cp_dparam[PROFF_SMC];
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/* Disable relocation */
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out_be16(&up->smc_rpbase, 0);
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/* Disable transmitter/receiver. */
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clrbits_be16(&sp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
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/* Enable SDMA. */
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out_be32(&im->im_siu_conf.sc_sdcr, 1);
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/* clear error conditions */
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out_8(&im->im_sdma.sdma_sdsr, CONFIG_SYS_SDSR);
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/* clear SDMA interrupt mask */
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out_8(&im->im_sdma.sdma_sdmr, CONFIG_SYS_SDMR);
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/* Use Port B for SMCx instead of other functions. */
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setbits_be32(&cp->cp_pbpar, IOPINS);
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clrbits_be32(&cp->cp_pbdir, IOPINS);
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clrbits_be16(&cp->cp_pbodr, IOPINS);
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/* Set the physical address of the host memory buffers in
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* the buffer descriptors.
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*/
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rtx = (struct serialbuffer __iomem *)&cp->cp_dpmem[CPM_SERIAL_BASE];
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/* Allocate space for two buffer descriptors in the DP ram.
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* For now, this address seems OK, but it may have to
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* change with newer versions of the firmware.
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* damm: allocating space after the two buffers for rx/tx data
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*/
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out_be32(&rtx->rxbd.cbd_bufaddr, (__force uint)&rtx->rxbuf);
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out_be16(&rtx->rxbd.cbd_sc, 0);
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out_be32(&rtx->txbd.cbd_bufaddr, (__force uint)&rtx->txbuf);
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out_be16(&rtx->txbd.cbd_sc, 0);
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/* Set up the uart parameters in the parameter ram. */
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out_be16(&up->smc_rbase, CPM_SERIAL_BASE);
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out_be16(&up->smc_tbase, CPM_SERIAL_BASE + sizeof(cbd_t));
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out_8(&up->smc_rfcr, SMC_EB);
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out_8(&up->smc_tfcr, SMC_EB);
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/* Set UART mode, 8 bit, no parity, one stop.
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* Enable receive and transmit.
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*/
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out_be16(&sp->smc_smcmr, smcr_mk_clen(9) | SMCMR_SM_UART);
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/* Mask all interrupts and remove anything pending.
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*/
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out_8(&sp->smc_smcm, 0);
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out_8(&sp->smc_smce, 0xff);
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/* Set up the baud rate generator */
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serial_mpc8xx_setbrg(dev, gd->baudrate);
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/* Make the first buffer the only buffer. */
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setbits_be16(&rtx->txbd.cbd_sc, BD_SC_WRAP);
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setbits_be16(&rtx->rxbd.cbd_sc, BD_SC_EMPTY | BD_SC_WRAP);
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/* single/multi character receive. */
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out_be16(&up->smc_mrblr, CONFIG_SYS_SMC_RXBUFLEN);
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out_be16(&up->smc_maxidl, CONFIG_SYS_MAXIDLE);
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out_be32(&rtx->rxindex, 0);
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/* Initialize Tx/Rx parameters. */
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while (in_be16(&cp->cp_cpcr) & CPM_CR_FLG) /* wait if cp is busy */
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;
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out_be16(&cp->cp_cpcr,
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mk_cr_cmd(CPM_CR_CH_SMC, CPM_CR_INIT_TRX) | CPM_CR_FLG);
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while (in_be16(&cp->cp_cpcr) & CPM_CR_FLG) /* wait if cp is busy */
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;
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/* Enable transmitter/receiver. */
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setbits_be16(&sp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
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return 0;
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}
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static int serial_mpc8xx_putc(struct udevice *dev, const char c)
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{
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immap_t __iomem *im = (immap_t __iomem *)CONFIG_SYS_IMMR;
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cpm8xx_t __iomem *cpmp = &(im->im_cpm);
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struct serialbuffer __iomem *rtx;
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rtx = (struct serialbuffer __iomem *)&cpmp->cp_dpmem[CPM_SERIAL_BASE];
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if (in_be16(&rtx->txbd.cbd_sc) & BD_SC_READY)
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return -EAGAIN;
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out_8(&rtx->txbuf, c);
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out_be16(&rtx->txbd.cbd_datlen, 1);
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setbits_be16(&rtx->txbd.cbd_sc, BD_SC_READY);
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return 0;
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}
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static int serial_mpc8xx_getc(struct udevice *dev)
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{
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immap_t __iomem *im = (immap_t __iomem *)CONFIG_SYS_IMMR;
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cpm8xx_t __iomem *cpmp = &(im->im_cpm);
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struct serialbuffer __iomem *rtx;
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unsigned char c;
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uint rxindex;
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rtx = (struct serialbuffer __iomem *)&cpmp->cp_dpmem[CPM_SERIAL_BASE];
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if (in_be16(&rtx->rxbd.cbd_sc) & BD_SC_EMPTY)
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return -EAGAIN;
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/* the characters are read one by one,
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* use the rxindex to know the next char to deliver
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*/
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rxindex = in_be32(&rtx->rxindex);
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c = in_8(rtx->rxbuf + rxindex);
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rxindex++;
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/* check if all char are readout, then make prepare for next receive */
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if (rxindex >= in_be16(&rtx->rxbd.cbd_datlen)) {
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rxindex = 0;
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setbits_be16(&rtx->rxbd.cbd_sc, BD_SC_EMPTY);
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}
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out_be32(&rtx->rxindex, rxindex);
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return c;
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}
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static int serial_mpc8xx_pending(struct udevice *dev, bool input)
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{
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immap_t __iomem *im = (immap_t __iomem *)CONFIG_SYS_IMMR;
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cpm8xx_t __iomem *cpmp = &(im->im_cpm);
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struct serialbuffer __iomem *rtx;
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if (!input)
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return 0;
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rtx = (struct serialbuffer __iomem *)&cpmp->cp_dpmem[CPM_SERIAL_BASE];
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return !(in_be16(&rtx->rxbd.cbd_sc) & BD_SC_EMPTY);
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}
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static const struct dm_serial_ops serial_mpc8xx_ops = {
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.putc = serial_mpc8xx_putc,
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.pending = serial_mpc8xx_pending,
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.getc = serial_mpc8xx_getc,
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.setbrg = serial_mpc8xx_setbrg,
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};
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static const struct udevice_id serial_mpc8xx_ids[] = {
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{ .compatible = "fsl,pq1-smc" },
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{ }
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};
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U_BOOT_DRIVER(serial_mpc8xx) = {
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.name = "serial_mpc8xx",
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.id = UCLASS_SERIAL,
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.of_match = serial_mpc8xx_ids,
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.probe = serial_mpc8xx_probe,
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.ops = &serial_mpc8xx_ops,
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.flags = DM_FLAG_PRE_RELOC,
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};
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