This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / arch / ppc / boot / simple / mpc52xx_tty.c

diff --git a/arch/ppc/boot/simple/mpc52xx_tty.c b/arch/ppc/boot/simple/mpc52xx_tty.c
new file mode 100644 (file)
index 0000000..8a1c663
--- /dev/null
+++ b/arch/ppc/boot/simple/mpc52xx_tty.c
@@ -0,0 +1,138 @@
+/*
+ * arch/ppc/boot/simple/mpc52xx_tty.c
+ *
+ * Minimal serial functions needed to send messages out a MPC52xx
+ * Programmable Serial Controller (PSC).
+ *
+ * Author: Dale Farnsworth <dfarnsworth@mvista.com>
+ *
+ * 2003-2004 (c) MontaVista, Software, Inc.  This file is licensed under the
+ * terms of the GNU General Public License version 2.  This program is licensed
+ * "as is" without any warranty of any kind, whether express or implied.
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <asm/uaccess.h>
+#include <asm/mpc52xx.h>
+#include <asm/mpc52xx_psc.h>
+#include <asm/serial.h>
+#include <asm/time.h>
+
+#if MPC52xx_PF_CONSOLE_PORT == 0
+#define MPC52xx_CONSOLE                MPC52xx_PSC1
+#define MPC52xx_PSC_CONFIG_SHIFT       0
+#elif MPC52xx_PF_CONSOLE_PORT == 1
+#define MPC52xx_CONSOLE                MPC52xx_PSC2
+#define MPC52xx_PSC_CONFIG_SHIFT       4
+#elif MPC52xx_PF_CONSOLE_PORT == 2
+#define MPC52xx_CONSOLE                MPC52xx_PSC3
+#define MPC52xx_PSC_CONFIG_SHIFT       8
+#else
+#error "MPC52xx_PF_CONSOLE_PORT not defined"
+#endif
+
+static struct mpc52xx_psc *psc = (struct mpc52xx_psc *)MPC52xx_CONSOLE;
+
+/* The decrementer counts at the system bus clock frequency
+ * divided by four.  The most accurate time base is connected to the
+ * rtc.  We read the decrementer change during one rtc tick (one second)
+ * and multiply by 4 to get the system bus clock frequency.
+ */
+int
+mpc52xx_ipbfreq(void)
+{
+       struct mpc52xx_rtc *rtc = (struct mpc52xx_rtc*)MPC52xx_RTC;
+       struct mpc52xx_cdm *cdm = (struct mpc52xx_cdm*)MPC52xx_CDM;
+       int current_time, previous_time;
+       int tbl_start, tbl_end;
+       int xlbfreq, ipbfreq;
+
+       out_be32(&rtc->dividers, 0x8f1f0000);   /* Set RTC 64x faster */
+       previous_time = in_be32(&rtc->time);
+       while ((current_time = in_be32(&rtc->time)) == previous_time) ;
+       tbl_start = get_tbl();
+       previous_time = current_time;
+       while ((current_time = in_be32(&rtc->time)) == previous_time) ;
+       tbl_end = get_tbl();
+       out_be32(&rtc->dividers, 0xffff0000);   /* Restore RTC */
+
+       xlbfreq = (tbl_end - tbl_start) << 8;
+       ipbfreq = (in_8(&cdm->ipb_clk_sel) & 1) ? xlbfreq / 2 : xlbfreq;
+
+       return ipbfreq;
+}
+
+unsigned long
+serial_init(int ignored, void *ignored2)
+{
+       struct mpc52xx_gpio *gpio = (struct mpc52xx_gpio *)MPC52xx_GPIO;
+       int divisor;
+       int mode1;
+       int mode2;
+       u32 val32;
+
+       static int been_here = 0;
+
+       if (been_here)
+               return 0;
+
+       been_here = 1;
+
+       val32 = in_be32(&gpio->port_config);
+       val32 &= ~(0x7 << MPC52xx_PSC_CONFIG_SHIFT);
+       val32 |= MPC52xx_GPIO_PSC_CONFIG_UART_WITHOUT_CD
+                               << MPC52xx_PSC_CONFIG_SHIFT;
+       out_be32(&gpio->port_config, val32);
+
+       out_8(&psc->command, MPC52xx_PSC_RST_TX
+                       | MPC52xx_PSC_RX_DISABLE | MPC52xx_PSC_TX_ENABLE);
+       out_8(&psc->command, MPC52xx_PSC_RST_RX);
+
+       out_be32(&psc->sicr, 0x0);
+       out_be16(&psc->mpc52xx_psc_clock_select, 0xdd00);
+       out_be16(&psc->tfalarm, 0xf8);
+
+       out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1
+                       | MPC52xx_PSC_RX_ENABLE
+                       | MPC52xx_PSC_TX_ENABLE);
+
+       divisor = ((mpc52xx_ipbfreq()
+                       / (CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD * 16)) + 1) >> 1;
+
+       mode1 = MPC52xx_PSC_MODE_8_BITS | MPC52xx_PSC_MODE_PARNONE
+                       | MPC52xx_PSC_MODE_ERR;
+       mode2 = MPC52xx_PSC_MODE_ONE_STOP;
+
+       out_8(&psc->ctur, divisor>>8);
+       out_8(&psc->ctlr, divisor);
+       out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
+       out_8(&psc->mode, mode1);
+       out_8(&psc->mode, mode2);
+
+       return 0;       /* ignored */
+}
+
+void
+serial_putc(void *ignored, const char c)
+{
+       serial_init(0, 0);
+
+       while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXEMP)) ;
+       out_8(&psc->mpc52xx_psc_buffer_8, c);
+       while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXEMP)) ;
+}
+
+char
+serial_getc(void *ignored)
+{
+       while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_RXRDY)) ;
+
+       return in_8(&psc->mpc52xx_psc_buffer_8);
+}
+
+int
+serial_tstc(void *ignored)
+{
+       return (in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_RXRDY) != 0;
+}