powerpc: Partialy restore core of mpc8xx

CS Systemes d'Information (CSSI) manufactures 8xx boards for
critical communication systems. Those boards have been
running U-Boot since 2010 and will have to be maintained
until at least 2027.

commit 5b8e76c35ec312a3f73126bd1a2d2c0965b98a9f
("powerpc, 8xx: remove support for 8xx") orphaned those boards
by removing support for the mpc8xx CPU.

This commit partially restores support for the 8xx, with the
following limitations:
- Restores support for MPC866 and MPC885 only
- Does not restore IDE, PCMCIA, I2C, USB
- Does not restore examples
- Does not restore POST
- Does not restore Ethernet on SCC
- Does not restore console on SCC
- Does not restore bedbug and kgdb support

As the 866 and 885 do not support the following features,
they are not restored either:
- VIDEO / LCD
- RTC clock

The CPM uCODE patch is not restored either, because:
- 866 and 885 already have support for I2C and SPI relocation
without a uCODE patch
- relocation of SMC, I2C or SPI is only needed for using SCCs
for Ethernet or QMC

The dynamic setup/calculation of clocks is removed, we
expect the target being use with the clock and PLPRCR register
defined in the configuration.
All the clock settings for 8xx prior to 866 is removed as
well as we now only support 866 and 885.

This code is mature and addresses mature boards. Therefore
all code enclosed in '#if 0/#endif' and '#if XX_DEBUG/#endif'
is unneeded.

The following files are not restored by this patch:

- arch/powerpc/cpu/mpc8xx/bedbug_860.c
- arch/powerpc/cpu/mpc8xx/fec.h
- arch/powerpc/cpu/mpc8xx/kgdb.S
- arch/powerpc/cpu/mpc8xx/plprcr_write.S
- arch/powerpc/cpu/mpc8xx/scc.c
- arch/powerpc/cpu/mpc8xx/upatch.c
- arch/powerpc/cpu/mpc8xx/video.c
- arch/powerpc/include/asm/status_led.h
- arch/powerpc/lib/ide.c
- arch/powerpc/lib/ide.h
- doc/README.MPC866
- drivers/pcmcia/mpc8xx_pcmcia.c
- drivers/rtc/mpc8xx.c
- drivers/usb/gadget/mpc8xx_udc.c
- drivers/video/mpc8xx_lcd.c
- examples/standalone/test_burst.c
- examples/standalone/test_burst.h
- examples/standalone/test_burst_lib.S
- examples/standalone/timer.c
- include/mpc823_lcd.h
- include/usb/mpc8xx_udc.h
- post/cpu/mpc8xx/Makefile
- post/cpu/mpc8xx/cache.c
- post/cpu/mpc8xx/cache_8xx.S
- post/cpu/mpc8xx/ether.c
- post/cpu/mpc8xx/spr.c
- post/cpu/mpc8xx/uart.c
- post/cpu/mpc8xx/usb.c
- post/cpu/mpc8xx/watchdog.c

Some of the restored files are not located in a proper location.
In order to keep traceability of the changes, they will be
moved to their correct location and moved to Kconfig in a
followup patch.

This patch also declares CSSI as point of contact for the update
of the 8xx platform, as those boards are the only ones still
being maintained on the 8xx area. A later patch will add
those boards to the tree.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
diff --git a/README b/README
index 54978c3..da9d472 100644
--- a/README
+++ b/README
@@ -324,6 +324,9 @@
 					  multiple fs option at one time
 					  for marvell soc family
 
+- 8xx CPU Options: (if using an MPC8xx CPU)
+		CONFIG_8xx_GCLK_FREQ	- CPU clock
+
 - 85xx CPU Options:
 		CONFIG_SYS_PPC64
 
@@ -687,10 +690,29 @@
 		Define this variable to enable hw flow control in serial driver.
 		Current user of this option is drivers/serial/nsl16550.c driver
 
+- Console Interface:
+		Depending on board, define exactly one serial port
+		(CONFIG_8xx_CONS_SMC1 or CONFIG_8xx_CONS_SMC2),
+		or switch off the serial console by defining
+		CONFIG_8xx_CONS_NONE
+
+		Note: if CONFIG_8xx_CONS_NONE is defined, the serial
+		port routines must be defined elsewhere
+		(i.e. serial_init(), serial_getc(), ...)
+
 - Console Baudrate:
 		CONFIG_BAUDRATE - in bps
 		Select one of the baudrates listed in
 		CONFIG_SYS_BAUDRATE_TABLE, see below.
+		CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
+
+- Console Rx buffer length
+		With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
+		the maximum receive buffer length for the SMC.
+		This option is actual only for 8xx possible.
+		If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
+		must be defined, to setup the maximum idle timeout for
+		the SMC.
 
 - Autoboot Command:
 		CONFIG_BOOTCOMMAND
@@ -856,7 +878,7 @@
 		(configuration option CONFIG_CMD_CACHE) unless you know
 		what you (and your U-Boot users) are doing. Data
 		cache cannot be enabled on systems like the
-		8260 (where accesses to the IMMR region must be
+		8xx (where accesses to the IMMR region must be
 		uncached), and it cannot be disabled on all other
 		systems where we (mis-) use the data cache to hold an
 		initial stack and some data.
@@ -919,9 +941,11 @@
 		CONFIG_WATCHDOG
 		If this variable is defined, it enables watchdog
 		support for the SoC. There must be support in the SoC
-		specific code for a watchdog. When supported for a
-		specific SoC is available, then no further board specific
-		code should be needed to use it.
+		specific code for a watchdog. For the 8xx
+		CPUs, the SIU Watchdog feature is enabled in the SYPCR
+		register.  When supported for a specific SoC is
+		available, then no further board specific code should
+		be needed to use it.
 
 		CONFIG_HW_WATCHDOG
 		When using a watchdog circuitry external to the used
@@ -3932,7 +3956,7 @@
 
 - CONFIG_SYS_IMMR:	Physical address of the Internal Memory.
 		DO NOT CHANGE unless you know exactly what you're
-		doing! (11-4) [82xx systems only]
+		doing! (11-4) [MPC8xx systems only]
 
 - CONFIG_SYS_INIT_RAM_ADDR:
 
@@ -3945,6 +3969,7 @@
 		sequences.
 
 		U-Boot uses the following memory types:
+		- MPC8xx: IMMR (internal memory of the CPU)
 
 - CONFIG_SYS_GBL_DATA_OFFSET:
 
@@ -3964,6 +3989,16 @@
 		point to an otherwise UNUSED address space between
 		the top of RAM and the start of the PCI space.
 
+- CONFIG_SYS_SIUMCR:	SIU Module Configuration (11-6)
+
+- CONFIG_SYS_SYPCR:	System Protection Control (11-9)
+
+- CONFIG_SYS_TBSCR:	Time Base Status and Control (11-26)
+
+- CONFIG_SYS_PISCR:	Periodic Interrupt Status and Control (11-31)
+
+- CONFIG_SYS_PLPRCR:	PLL, Low-Power, and Reset Control Register (15-30)
+
 - CONFIG_SYS_SCCR:	System Clock and reset Control Register (15-27)
 
 - CONFIG_SYS_OR_TIMING_SDRAM:
@@ -3972,6 +4007,8 @@
 - CONFIG_SYS_MAMR_PTA:
 		periodic timer for refresh
 
+- CONFIG_SYS_DER:	Debug Event Register (37-47)
+
 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
   CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
   CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
@@ -4057,6 +4094,21 @@
 		Only for 83xx systems. If specified, then DDR should
 		be configured using CS0 and CS1 instead of CS2 and CS3.
 
+- CONFIG_ETHER_ON_FEC[12]
+		Define to enable FEC[12] on a 8xx series processor.
+
+- CONFIG_FEC[12]_PHY
+		Define to the hardcoded PHY address which corresponds
+		to the given FEC; i. e.
+			#define CONFIG_FEC1_PHY 4
+		means that the PHY with address 4 is connected to FEC1
+
+		When set to -1, means to probe for first available.
+
+- CONFIG_FEC[12]_PHY_NORXERR
+		The PHY does not have a RXERR line (RMII only).
+		(so program the FEC to ignore it).
+
 - CONFIG_RMII
 		Enable RMII mode for all FECs.
 		Note that this is a global option, we can't