[PATCH] powerpc: Move udbg code to arch/powerpc

Since the udbg code in ppc64 has no ppc32 equivalent, move it straight
over into arch/powerpc (and include/asm-powerpc for udbg.h).  In time,
we probably want to meld the various bits and pieces of 32-bit early
debugging code into udbg, but for now only include it on
CONFIG_PPC64=y builds.  The only change during the move is to
standardise the protecting #ifdef/#define in udbg.h, and move its
banner comment above the initial #ifdef (which seems to be normal
practice).

Built and booted on POWER5 LPAR (ARCH=powerpc and ARCH=ppc64).  Built
for 32bit multiplatform (ARCH=powerpc).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

4 files changed, 388 insertions, 1 deletions

diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index c04bbd320594..c68eace12a9d 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -16,7 +16,7 @@ obj-y				:= semaphore.o cputable.o ptrace.o syscalls.o \
 obj-$(CONFIG_PPC64)             += setup_64.o binfmt_elf32.o sys_ppc32.o \
                                    signal_64.o ptrace32.o systbl.o \
                                    paca.o ioctl32.o cpu_setup_power4.o \
-                                   firmware.o sysfs.o
+                                   firmware.o sysfs.o udbg.o
 obj-$(CONFIG_ALTIVEC)           += vecemu.o vector.o
 obj-$(CONFIG_POWER4)            += idle_power4.o
 obj-$(CONFIG_PPC_OF)            += of_device.o
@@ -29,6 +29,10 @@ obj-$(CONFIG_RTAS_PROC)		+= rtas-proc.o
 obj-$(CONFIG_LPARCFG)           += lparcfg.o
 obj-$(CONFIG_IBMVIO)            += vio.o
 obj-$(CONFIG_GENERIC_TBSYNC)    += smp-tbsync.o
+obj-$(CONFIG_PPC_PSERIES)       += udbg_16550.o
+obj-$(CONFIG_PPC_MAPLE)         += udbg_16550.o
+udbgscc-$(CONFIG_PPC64)         := udbg_scc.o
+obj-$(CONFIG_PPC_PMAC)          += $(udbgscc-y)
 
 ifeq ($(CONFIG_PPC_MERGE),y)
 
diff --git a/arch/powerpc/kernel/udbg.c b/arch/powerpc/kernel/udbg.c
new file mode 100644
index 000000000000..0d878e72fc44
--- /dev/null
+++ b/arch/powerpc/kernel/udbg.c
@@ -0,0 +1,125 @@
+/*
+ * polling mode stateless debugging stuff, originally for NS16550 Serial Ports
+ *
+ * c 2001 PPC 64 Team, IBM Corp
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#include <stdarg.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/console.h>
+#include <asm/processor.h>
+
+void (*udbg_putc)(unsigned char c);
+unsigned char (*udbg_getc)(void);
+int (*udbg_getc_poll)(void);
+
+/* udbg library, used by xmon et al */
+void udbg_puts(const char *s)
+{
+        if (udbg_putc) {
+                char c;
+
+                if (s && *s != '\0') {
+                        while ((c = *s++) != '\0')
+                                udbg_putc(c);
+                }
+        }
+#if 0
+        else {
+                printk("%s", s);
+        }
+#endif
+}
+
+int udbg_write(const char *s, int n)
+{
+        int remain = n;
+        char c;
+
+        if (!udbg_putc)
+                return 0;
+
+        if (s && *s != '\0') {
+                while (((c = *s++) != '\0') && (remain-- > 0)) {
+                        udbg_putc(c);
+                }
+        }
+
+        return n - remain;
+}
+
+int udbg_read(char *buf, int buflen)
+{
+        char c, *p = buf;
+        int i;
+
+        if (!udbg_getc)
+                return 0;
+
+        for (i = 0; i < buflen; ++i) {
+                do {
+                        c = udbg_getc();
+                } while (c == 0x11 || c == 0x13);
+                if (c == 0)
+                        break;
+                *p++ = c;
+        }
+
+        return i;
+}
+
+#define UDBG_BUFSIZE 256
+void udbg_printf(const char *fmt, ...)
+{
+        unsigned char buf[UDBG_BUFSIZE];
+        va_list args;
+
+        va_start(args, fmt);
+        vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
+        udbg_puts(buf);
+        va_end(args);
+}
+
+/*
+ * Early boot console based on udbg
+ */
+static void udbg_console_write(struct console *con, const char *s,
+                unsigned int n)
+{
+        udbg_write(s, n);
+}
+
+static struct console udbg_console = {
+        .name   = "udbg",
+        .write  = udbg_console_write,
+        .flags  = CON_PRINTBUFFER,
+        .index  = -1,
+};
+
+static int early_console_initialized;
+
+void __init disable_early_printk(void)
+{
+        if (!early_console_initialized)
+                return;
+        unregister_console(&udbg_console);
+        early_console_initialized = 0;
+}
+
+/* called by setup_system */
+void register_early_udbg_console(void)
+{
+        early_console_initialized = 1;
+        register_console(&udbg_console);
+}
+
+#if 0   /* if you want to use this as a regular output console */
+console_initcall(register_udbg_console);
+#endif
diff --git a/arch/powerpc/kernel/udbg_16550.c b/arch/powerpc/kernel/udbg_16550.c
new file mode 100644
index 000000000000..9313574ab935
--- /dev/null
+++ b/arch/powerpc/kernel/udbg_16550.c
@@ -0,0 +1,123 @@
+/*
+ * udbg for for NS16550 compatable serial ports
+ *
+ * Copyright (C) 2001-2005 PPC 64 Team, IBM Corp
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+#include <linux/config.h>
+#include <linux/types.h>
+#include <asm/udbg.h>
+#include <asm/io.h>
+
+extern u8 real_readb(volatile u8 __iomem  *addr);
+extern void real_writeb(u8 data, volatile u8 __iomem *addr);
+
+struct NS16550 {
+        /* this struct must be packed */
+        unsigned char rbr;  /* 0 */
+        unsigned char ier;  /* 1 */
+        unsigned char fcr;  /* 2 */
+        unsigned char lcr;  /* 3 */
+        unsigned char mcr;  /* 4 */
+        unsigned char lsr;  /* 5 */
+        unsigned char msr;  /* 6 */
+        unsigned char scr;  /* 7 */
+};
+
+#define thr rbr
+#define iir fcr
+#define dll rbr
+#define dlm ier
+#define dlab lcr
+
+#define LSR_DR   0x01  /* Data ready */
+#define LSR_OE   0x02  /* Overrun */
+#define LSR_PE   0x04  /* Parity error */
+#define LSR_FE   0x08  /* Framing error */
+#define LSR_BI   0x10  /* Break */
+#define LSR_THRE 0x20  /* Xmit holding register empty */
+#define LSR_TEMT 0x40  /* Xmitter empty */
+#define LSR_ERR  0x80  /* Error */
+
+static volatile struct NS16550 __iomem *udbg_comport;
+
+static void udbg_550_putc(unsigned char c)
+{
+        if (udbg_comport) {
+                while ((in_8(&udbg_comport->lsr) & LSR_THRE) == 0)
+                        /* wait for idle */;
+                out_8(&udbg_comport->thr, c);
+                if (c == '\n')
+                        udbg_550_putc('\r');
+        }
+}
+
+static int udbg_550_getc_poll(void)
+{
+        if (udbg_comport) {
+                if ((in_8(&udbg_comport->lsr) & LSR_DR) != 0)
+                        return in_8(&udbg_comport->rbr);
+                else
+                        return -1;
+        }
+        return -1;
+}
+
+static unsigned char udbg_550_getc(void)
+{
+        if (udbg_comport) {
+                while ((in_8(&udbg_comport->lsr) & LSR_DR) == 0)
+                        /* wait for char */;
+                return in_8(&udbg_comport->rbr);
+        }
+        return 0;
+}
+
+void udbg_init_uart(void __iomem *comport, unsigned int speed)
+{
+        u16 dll = speed ? (115200 / speed) : 12;
+
+        if (comport) {
+                udbg_comport = (struct NS16550 __iomem *)comport;
+                out_8(&udbg_comport->lcr, 0x00);
+                out_8(&udbg_comport->ier, 0xff);
+                out_8(&udbg_comport->ier, 0x00);
+                out_8(&udbg_comport->lcr, 0x80);        /* Access baud rate */
+                out_8(&udbg_comport->dll, dll & 0xff);  /* 1 = 115200,  2 = 57600,
+                                                           3 = 38400, 12 = 9600 baud */
+                out_8(&udbg_comport->dlm, dll >> 8);    /* dll >> 8 which should be zero
+                                                           for fast rates; */
+                out_8(&udbg_comport->lcr, 0x03);        /* 8 data, 1 stop, no parity */
+                out_8(&udbg_comport->mcr, 0x03);        /* RTS/DTR */
+                out_8(&udbg_comport->fcr ,0x07);        /* Clear & enable FIFOs */
+                udbg_putc = udbg_550_putc;
+                udbg_getc = udbg_550_getc;
+                udbg_getc_poll = udbg_550_getc_poll;
+        }
+}
+
+#ifdef CONFIG_PPC_MAPLE
+void udbg_maple_real_putc(unsigned char c)
+{
+        if (udbg_comport) {
+                while ((real_readb(&udbg_comport->lsr) & LSR_THRE) == 0)
+                        /* wait for idle */;
+                real_writeb(c, &udbg_comport->thr); eieio();
+                if (c == '\n')
+                        udbg_maple_real_putc('\r');
+        }
+}
+
+void udbg_init_maple_realmode(void)
+{
+        udbg_comport = (volatile struct NS16550 __iomem *)0xf40003f8;
+
+        udbg_putc = udbg_maple_real_putc;
+        udbg_getc = NULL;
+        udbg_getc_poll = NULL;
+}
+#endif /* CONFIG_PPC_MAPLE */
diff --git a/arch/powerpc/kernel/udbg_scc.c b/arch/powerpc/kernel/udbg_scc.c
new file mode 100644
index 000000000000..820c53551507
--- /dev/null
+++ b/arch/powerpc/kernel/udbg_scc.c
@@ -0,0 +1,135 @@
+/*
+ * udbg for for zilog scc ports as found on Apple PowerMacs
+ *
+ * Copyright (C) 2001-2005 PPC 64 Team, IBM Corp
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+#include <linux/config.h>
+#include <linux/types.h>
+#include <asm/udbg.h>
+#include <asm/processor.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/pmac_feature.h>
+
+extern u8 real_readb(volatile u8 __iomem  *addr);
+extern void real_writeb(u8 data, volatile u8 __iomem *addr);
+
+#define SCC_TXRDY       4
+#define SCC_RXRDY       1
+
+static volatile u8 __iomem *sccc;
+static volatile u8 __iomem *sccd;
+
+static void udbg_scc_putc(unsigned char c)
+{
+        if (sccc) {
+                while ((in_8(sccc) & SCC_TXRDY) == 0)
+                        ;
+                out_8(sccd,  c);
+                if (c == '\n')
+                        udbg_scc_putc('\r');
+        }
+}
+
+static int udbg_scc_getc_poll(void)
+{
+        if (sccc) {
+                if ((in_8(sccc) & SCC_RXRDY) != 0)
+                        return in_8(sccd);
+                else
+                        return -1;
+        }
+        return -1;
+}
+
+static unsigned char udbg_scc_getc(void)
+{
+        if (sccc) {
+                while ((in_8(sccc) & SCC_RXRDY) == 0)
+                        ;
+                return in_8(sccd);
+        }
+        return 0;
+}
+
+static unsigned char scc_inittab[] = {
+    13, 0,              /* set baud rate divisor */
+    12, 0,
+    14, 1,              /* baud rate gen enable, src=rtxc */
+    11, 0x50,           /* clocks = br gen */
+    5,  0xea,           /* tx 8 bits, assert DTR & RTS */
+    4,  0x46,           /* x16 clock, 1 stop */
+    3,  0xc1,           /* rx enable, 8 bits */
+};
+
+void udbg_init_scc(struct device_node *np)
+{
+        u32 *reg;
+        unsigned long addr;
+        int i, x;
+
+        if (np == NULL)
+                np = of_find_node_by_name(NULL, "escc");
+        if (np == NULL || np->parent == NULL)
+                return;
+
+        udbg_printf("found SCC...\n");
+        /* Get address within mac-io ASIC */
+        reg = (u32 *)get_property(np, "reg", NULL);
+        if (reg == NULL)
+                return;
+        addr = reg[0];
+        udbg_printf("local addr: %lx\n", addr);
+        /* Get address of mac-io PCI itself */
+        reg = (u32 *)get_property(np->parent, "assigned-addresses", NULL);
+        if (reg == NULL)
+                return;
+        addr += reg[2];
+        udbg_printf("final addr: %lx\n", addr);
+
+        /* Setup for 57600 8N1 */
+        addr += 0x20;
+        sccc = (volatile u8 * __iomem) ioremap(addr & PAGE_MASK, PAGE_SIZE) ;
+        sccc += addr & ~PAGE_MASK;
+        sccd = sccc + 0x10;
+
+        udbg_printf("ioremap result sccc: %p\n", sccc);
+        mb();
+
+        for (i = 20000; i != 0; --i)
+                x = in_8(sccc);
+        out_8(sccc, 0x09);              /* reset A or B side */
+        out_8(sccc, 0xc0);
+        for (i = 0; i < sizeof(scc_inittab); ++i)
+                out_8(sccc, scc_inittab[i]);
+
+        udbg_putc = udbg_scc_putc;
+        udbg_getc = udbg_scc_getc;
+        udbg_getc_poll = udbg_scc_getc_poll;
+
+        udbg_puts("Hello World !\n");
+}
+
+static void udbg_real_scc_putc(unsigned char c)
+{
+        while ((real_readb(sccc) & SCC_TXRDY) == 0)
+                ;
+        real_writeb(c, sccd);
+        if (c == '\n')
+                udbg_real_scc_putc('\r');
+}
+
+void udbg_init_pmac_realmode(void)
+{
+        sccc = (volatile u8 __iomem *)0x80013020ul;
+        sccd = (volatile u8 __iomem *)0x80013030ul;
+
+        udbg_putc = udbg_real_scc_putc;
+        udbg_getc = NULL;
+        udbg_getc_poll = NULL;
+}