1 files changed, 301 insertions, 0 deletions
diff --git a/arch/powerpc/cpu/mpc8xx/serial.c b/arch/powerpc/cpu/mpc8xx/serial.c
new file mode 100644
index 0000000000..d4f1a41a1a
--- /dev/null
+++ b/arch/powerpc/cpu/mpc8xx/serial.c
@@ -0,0 +1,301 @@
+/*
+ * (C) Copyright 2000
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <commproc.h>
+#include <command.h>
+#include <serial.h>
+#include <watchdog.h>
+#include <linux/compiler.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#if !defined(CONFIG_8xx_CONS_NONE)	/* No Console at all */
+
+#if defined(CONFIG_8xx_CONS_SMC1)	/* Console on SMC1 */
+#define	SMC_INDEX	0
+#define PROFF_SMC	PROFF_SMC1
+#define CPM_CR_CH_SMC	CPM_CR_CH_SMC1
+
+#elif defined(CONFIG_8xx_CONS_SMC2)	/* Console on SMC2 */
+#define SMC_INDEX	1
+#define PROFF_SMC	PROFF_SMC2
+#define CPM_CR_CH_SMC	CPM_CR_CH_SMC2
+
+#endif /* CONFIG_8xx_CONS_SMCx */
+
+#if !defined(CONFIG_SYS_SMC_RXBUFLEN)
+#define CONFIG_SYS_SMC_RXBUFLEN	1
+#define CONFIG_SYS_MAXIDLE	0
+#else
+#if !defined(CONFIG_SYS_MAXIDLE)
+#error "you must define CONFIG_SYS_MAXIDLE"
+#endif
+#endif
+
+typedef volatile struct serialbuffer {
+	cbd_t	rxbd;		/* Rx BD */
+	cbd_t	txbd;		/* Tx BD */
+	uint	rxindex;	/* index for next character to read */
+	volatile uchar	rxbuf[CONFIG_SYS_SMC_RXBUFLEN];/* rx buffers */
+	volatile uchar	txbuf;	/* tx buffers */
+} serialbuffer_t;
+
+static void serial_setdivisor(volatile cpm8xx_t *cp)
+{
+	int divisor=(gd->cpu_clk + 8*gd->baudrate)/16/gd->baudrate;
+
+	if(divisor/16>0x1000) {
+		/* bad divisor, assume 50MHz clock and 9600 baud */
+		divisor=(50*1000*1000 + 8*9600)/16/9600;
+	}
+
+#ifdef CONFIG_SYS_BRGCLK_PRESCALE
+	divisor /= CONFIG_SYS_BRGCLK_PRESCALE;
+#endif
+
+	if(divisor<=0x1000) {
+		cp->cp_brgc1=((divisor-1)<<1) | CPM_BRG_EN;
+	} else {
+		cp->cp_brgc1=((divisor/16-1)<<1) | CPM_BRG_EN | CPM_BRG_DIV16;
+	}
+}
+
+/*
+ * Minimal serial functions needed to use one of the SMC ports
+ * as serial console interface.
+ */
+
+static void smc_setbrg (void)
+{
+	volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
+	volatile cpm8xx_t *cp = &(im->im_cpm);
+
+	/* Set up the baud rate generator.
+	 * See 8xx_io/commproc.c for details.
+	 *
+	 * Wire BRG1 to SMCx
+	 */
+
+	cp->cp_simode = 0x00000000;
+
+	serial_setdivisor(cp);
+}
+
+static int smc_init (void)
+{
+	volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
+	volatile smc_t *sp;
+	volatile smc_uart_t *up;
+	volatile cpm8xx_t *cp = &(im->im_cpm);
+	uint	dpaddr;
+	volatile serialbuffer_t *rtx;
+
+	/* initialize pointers to SMC */
+
+	sp = (smc_t *) &(cp->cp_smc[SMC_INDEX]);
+	up = (smc_uart_t *) &cp->cp_dparam[PROFF_SMC];
+	/* Disable relocation */
+	up->smc_rpbase = 0;
+
+	/* Disable transmitter/receiver. */
+	sp->smc_smcmr &= ~(SMCMR_REN | SMCMR_TEN);
+
+	/* Enable SDMA. */
+	im->im_siu_conf.sc_sdcr = 1;
+
+	/* clear error conditions */
+#ifdef	CONFIG_SYS_SDSR
+	im->im_sdma.sdma_sdsr = CONFIG_SYS_SDSR;
+#else
+	im->im_sdma.sdma_sdsr = 0x83;
+#endif
+
+	/* clear SDMA interrupt mask */
+#ifdef	CONFIG_SYS_SDMR
+	im->im_sdma.sdma_sdmr = CONFIG_SYS_SDMR;
+#else
+	im->im_sdma.sdma_sdmr = 0x00;
+#endif
+
+#if defined(CONFIG_8xx_CONS_SMC1)
+	/* Use Port B for SMC1 instead of other functions. */
+	cp->cp_pbpar |=  0x000000c0;
+	cp->cp_pbdir &= ~0x000000c0;
+	cp->cp_pbodr &= ~0x000000c0;
+#else	/* CONFIG_8xx_CONS_SMC2 */
+	/* Use Port B for SMC2 instead of other functions.
+	 */
+	cp->cp_pbpar |=  0x00000c00;
+	cp->cp_pbdir &= ~0x00000c00;
+	cp->cp_pbodr &= ~0x00000c00;
+#endif
+
+	/* Set the physical address of the host memory buffers in
+	 * the buffer descriptors.
+	 */
+	dpaddr = CPM_SERIAL_BASE;
+
+	rtx = (serialbuffer_t *)&cp->cp_dpmem[dpaddr];
+	/* 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.
+	 * damm: allocating space after the two buffers for rx/tx data
+	 */
+
+	rtx->rxbd.cbd_bufaddr = (uint) &rtx->rxbuf;
+	rtx->rxbd.cbd_sc      = 0;
+
+	rtx->txbd.cbd_bufaddr = (uint) &rtx->txbuf;
+	rtx->txbd.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 */
+	smc_setbrg ();
+
+	/* Make the first buffer the only buffer. */
+	rtx->txbd.cbd_sc |= BD_SC_WRAP;
+	rtx->rxbd.cbd_sc |= BD_SC_EMPTY | BD_SC_WRAP;
+
+	/* single/multi character receive. */
+	up->smc_mrblr = CONFIG_SYS_SMC_RXBUFLEN;
+	up->smc_maxidl = CONFIG_SYS_MAXIDLE;
+	rtx->rxindex = 0;
+
+	/* Initialize Tx/Rx parameters.	*/
+	while (cp->cp_cpcr & CPM_CR_FLG)  /* wait if cp is busy */
+	  ;
+
+	cp->cp_cpcr = mk_cr_cmd(CPM_CR_CH_SMC, CPM_CR_INIT_TRX) | CPM_CR_FLG;
+
+	while (cp->cp_cpcr & CPM_CR_FLG)  /* wait if cp is busy */
+	  ;
+
+	/* Enable transmitter/receiver.	*/
+	sp->smc_smcmr |= SMCMR_REN | SMCMR_TEN;
+
+	return (0);
+}
+
+static void
+smc_putc(const char c)
+{
+	volatile smc_uart_t	*up;
+	volatile immap_t	*im = (immap_t *)CONFIG_SYS_IMMR;
+	volatile cpm8xx_t	*cpmp = &(im->im_cpm);
+	volatile serialbuffer_t	*rtx;
+
+	if (c == '\n')
+		smc_putc ('\r');
+
+	up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_SMC];
+
+	rtx = (serialbuffer_t *)&cpmp->cp_dpmem[up->smc_rbase];
+
+	/* Wait for last character to go. */
+	rtx->txbuf = c;
+	rtx->txbd.cbd_datlen = 1;
+	rtx->txbd.cbd_sc |= BD_SC_READY;
+	__asm__("eieio");
+
+	while (rtx->txbd.cbd_sc & BD_SC_READY) {
+		WATCHDOG_RESET ();
+		__asm__("eieio");
+	}
+}
+
+static void
+smc_puts (const char *s)
+{
+	while (*s) {
+		smc_putc (*s++);
+	}
+}
+
+static int
+smc_getc(void)
+{
+	volatile smc_uart_t	*up;
+	volatile immap_t	*im = (immap_t *)CONFIG_SYS_IMMR;
+	volatile cpm8xx_t	*cpmp = &(im->im_cpm);
+	volatile serialbuffer_t	*rtx;
+	unsigned char  c;
+
+	up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_SMC];
+	rtx = (serialbuffer_t *)&cpmp->cp_dpmem[up->smc_rbase];
+
+	/* Wait for character to show up. */
+	while (rtx->rxbd.cbd_sc & BD_SC_EMPTY)
+		WATCHDOG_RESET ();
+
+	/* the characters are read one by one,
+	 * use the rxindex to know the next char to deliver
+	 */
+	c = *(unsigned char *) (rtx->rxbd.cbd_bufaddr+rtx->rxindex);
+	rtx->rxindex++;
+
+	/* check if all char are readout, then make prepare for next receive */
+	if (rtx->rxindex >= rtx->rxbd.cbd_datlen) {
+		rtx->rxindex = 0;
+		rtx->rxbd.cbd_sc |= BD_SC_EMPTY;
+	}
+	return(c);
+}
+
+static int
+smc_tstc(void)
+{
+	volatile smc_uart_t	*up;
+	volatile immap_t	*im = (immap_t *)CONFIG_SYS_IMMR;
+	volatile cpm8xx_t	*cpmp = &(im->im_cpm);
+	volatile serialbuffer_t	*rtx;
+
+	up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_SMC];
+
+	rtx = (serialbuffer_t *)&cpmp->cp_dpmem[up->smc_rbase];
+
+	return !(rtx->rxbd.cbd_sc & BD_SC_EMPTY);
+}
+
+struct serial_device serial_smc_device =
+{
+	.name	= "serial_smc",
+	.start	= smc_init,
+	.stop	= NULL,
+	.setbrg	= smc_setbrg,
+	.getc	= smc_getc,
+	.tstc	= smc_tstc,
+	.putc	= smc_putc,
+	.puts	= smc_puts,
+};
+
+__weak struct serial_device *default_serial_console(void)
+{
+	return &serial_smc_device;
+}
+
+void mpc8xx_serial_initialize(void)
+{
+	serial_register(&serial_smc_device);
+}
+
+#endif	/* CONFIG_8xx_CONS_NONE */