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authorKars de Jong <jongk@linux-m68k.org>2008-11-20 13:47:18 +0100
committerGeert Uytterhoeven <geert@linux-m68k.org>2011-12-10 19:52:45 +0100
commitf9994894953d6bd9d5ed2719a34d027a4e0c2131 (patch)
tree07c0ba833ae382e95dd391a598b3117bef27f6a8 /arch/m68k
parentf8bd9de913fc004705002f7bd6e840b1c685b188 (diff)
downloadop-kernel-dev-f9994894953d6bd9d5ed2719a34d027a4e0c2131.zip
op-kernel-dev-f9994894953d6bd9d5ed2719a34d027a4e0c2131.tar.gz
m68k/mvme16x: Add support for EARLY_PRINTK
Added support for EARLY_PRINTK when running on an MVME16x board. Signed-off-by: Kars de Jong <jongk@linux-m68k.org> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Diffstat (limited to 'arch/m68k')
-rw-r--r--arch/m68k/Kconfig.debug11
-rw-r--r--arch/m68k/mvme16x/config.c160
2 files changed, 171 insertions, 0 deletions
diff --git a/arch/m68k/Kconfig.debug b/arch/m68k/Kconfig.debug
index 2bdb1b0..8702dc6 100644
--- a/arch/m68k/Kconfig.debug
+++ b/arch/m68k/Kconfig.debug
@@ -2,6 +2,17 @@ menu "Kernel hacking"
source "lib/Kconfig.debug"
+config EARLY_PRINTK
+ bool "Early printk" if EMBEDDED
+ depends on MVME16x
+ default y
+ help
+ Write kernel log output directly to a serial port.
+
+ This is useful for kernel debugging when your machine crashes very
+ early before the console code is initialized.
+ You should normally say N here, unless you want to debug such a crash.
+
if !MMU
config FULLDEBUG
diff --git a/arch/m68k/mvme16x/config.c b/arch/m68k/mvme16x/config.c
index 31a66d9..c3fb3bd 100644
--- a/arch/m68k/mvme16x/config.c
+++ b/arch/m68k/mvme16x/config.c
@@ -124,6 +124,163 @@ static void __init mvme16x_init_IRQ (void)
#define PccSCCMICR 0x1d
#define PccSCCTICR 0x1e
#define PccSCCRICR 0x1f
+#define PccTPIACKR 0x25
+
+#ifdef CONFIG_EARLY_PRINTK
+
+/**** cd2401 registers ****/
+#define CD2401_ADDR (0xfff45000)
+
+#define CyGFRCR (0x81)
+#define CyCCR (0x13)
+#define CyCLR_CHAN (0x40)
+#define CyINIT_CHAN (0x20)
+#define CyCHIP_RESET (0x10)
+#define CyENB_XMTR (0x08)
+#define CyDIS_XMTR (0x04)
+#define CyENB_RCVR (0x02)
+#define CyDIS_RCVR (0x01)
+#define CyCAR (0xee)
+#define CyIER (0x11)
+#define CyMdmCh (0x80)
+#define CyRxExc (0x20)
+#define CyRxData (0x08)
+#define CyTxMpty (0x02)
+#define CyTxRdy (0x01)
+#define CyLICR (0x26)
+#define CyRISR (0x89)
+#define CyTIMEOUT (0x80)
+#define CySPECHAR (0x70)
+#define CyOVERRUN (0x08)
+#define CyPARITY (0x04)
+#define CyFRAME (0x02)
+#define CyBREAK (0x01)
+#define CyREOIR (0x84)
+#define CyTEOIR (0x85)
+#define CyMEOIR (0x86)
+#define CyNOTRANS (0x08)
+#define CyRFOC (0x30)
+#define CyRDR (0xf8)
+#define CyTDR (0xf8)
+#define CyMISR (0x8b)
+#define CyRISR (0x89)
+#define CyTISR (0x8a)
+#define CyMSVR1 (0xde)
+#define CyMSVR2 (0xdf)
+#define CyDSR (0x80)
+#define CyDCD (0x40)
+#define CyCTS (0x20)
+#define CyDTR (0x02)
+#define CyRTS (0x01)
+#define CyRTPRL (0x25)
+#define CyRTPRH (0x24)
+#define CyCOR1 (0x10)
+#define CyPARITY_NONE (0x00)
+#define CyPARITY_E (0x40)
+#define CyPARITY_O (0xC0)
+#define Cy_5_BITS (0x04)
+#define Cy_6_BITS (0x05)
+#define Cy_7_BITS (0x06)
+#define Cy_8_BITS (0x07)
+#define CyCOR2 (0x17)
+#define CyETC (0x20)
+#define CyCtsAE (0x02)
+#define CyCOR3 (0x16)
+#define Cy_1_STOP (0x02)
+#define Cy_2_STOP (0x04)
+#define CyCOR4 (0x15)
+#define CyREC_FIFO (0x0F) /* Receive FIFO threshold */
+#define CyCOR5 (0x14)
+#define CyCOR6 (0x18)
+#define CyCOR7 (0x07)
+#define CyRBPR (0xcb)
+#define CyRCOR (0xc8)
+#define CyTBPR (0xc3)
+#define CyTCOR (0xc0)
+#define CySCHR1 (0x1f)
+#define CySCHR2 (0x1e)
+#define CyTPR (0xda)
+#define CyPILR1 (0xe3)
+#define CyPILR2 (0xe0)
+#define CyPILR3 (0xe1)
+#define CyCMR (0x1b)
+#define CyASYNC (0x02)
+#define CyLICR (0x26)
+#define CyLIVR (0x09)
+#define CySCRL (0x23)
+#define CySCRH (0x22)
+#define CyTFTC (0x80)
+
+static void cons_write(struct console *co, const char *str, unsigned count)
+{
+ volatile unsigned char *base_addr = (u_char *)CD2401_ADDR;
+ volatile u_char sink;
+ u_char ier;
+ int port;
+ u_char do_lf = 0;
+ int i = 0;
+
+ /* Ensure transmitter is enabled! */
+
+ port = 0;
+ base_addr[CyCAR] = (u_char)port;
+ while (base_addr[CyCCR])
+ ;
+ base_addr[CyCCR] = CyENB_XMTR;
+
+ ier = base_addr[CyIER];
+ base_addr[CyIER] = CyTxMpty;
+
+ while (1) {
+ if (pcc2chip[PccSCCTICR] & 0x20)
+ {
+ /* We have a Tx int. Acknowledge it */
+ sink = pcc2chip[PccTPIACKR];
+ if ((base_addr[CyLICR] >> 2) == port) {
+ if (i == count) {
+ /* Last char of string is now output */
+ base_addr[CyTEOIR] = CyNOTRANS;
+ break;
+ }
+ if (do_lf) {
+ base_addr[CyTDR] = '\n';
+ str++;
+ i++;
+ do_lf = 0;
+ }
+ else if (*str == '\n') {
+ base_addr[CyTDR] = '\r';
+ do_lf = 1;
+ }
+ else {
+ base_addr[CyTDR] = *str++;
+ i++;
+ }
+ base_addr[CyTEOIR] = 0;
+ }
+ else
+ base_addr[CyTEOIR] = CyNOTRANS;
+ }
+ }
+
+ base_addr[CyIER] = ier;
+}
+
+static struct console cons_info =
+{
+ .name = "sercon",
+ .write = cons_write,
+ .flags = CON_PRINTBUFFER | CON_BOOT,
+ .index = -1,
+};
+
+static void __init mvme16x_early_console(void)
+{
+ register_console(&cons_info);
+
+ printk(KERN_INFO "MVME16x: early console registered\n");
+}
+#endif
void __init config_mvme16x(void)
{
@@ -183,6 +340,9 @@ void __init config_mvme16x(void)
pcc2chip[PccSCCMICR] = 0x10;
pcc2chip[PccSCCTICR] = 0x10;
pcc2chip[PccSCCRICR] = 0x10;
+#ifdef CONFIG_EARLY_PRINTK
+ mvme16x_early_console();
+#endif
}
}
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