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authorDavid Gibson <david@gibson.dropbear.id.au>2005-11-11 16:42:12 +1100
committerPaul Mackerras <paulus@samba.org>2005-11-11 22:23:34 +1100
commit35cd8785de39c90a52287d0f041cff8a792eaa74 (patch)
treee45b94be971992d21f06086ef2ae443b90fd621b /arch/powerpc/kernel/udbg_16550.c
parenta7df61a0e2b6300d8b8349c1e5e87a4336c0ab38 (diff)
downloadlinux-35cd8785de39c90a52287d0f041cff8a792eaa74.tar.bz2
[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>
Diffstat (limited to 'arch/powerpc/kernel/udbg_16550.c')
-rw-r--r--arch/powerpc/kernel/udbg_16550.c123
1 files changed, 123 insertions, 0 deletions
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 */