blob: 097aa4a5e74882a91214416f3af5c740df47fa0c [file] [log] [blame] [edit]
/*
* SPDX-License-Identifier: GPL-2.0 IBM-pibs
*/
#include <config.h>
#include <asm/ppc4xx.h>
#include <ppc_asm.tmpl>
#include <ppc_defs.h>
#include <asm/cache.h>
#include <asm/mmu.h>
/**
* ext_bus_cntlr_init - Initializes the External Bus Controller for the external peripherals
*
* IMPORTANT: For pass1 this code must run from cache since you can not
* reliably change a peripheral banks timing register (pbxap) while running
* code from that bank. For ex., since we are running from ROM on bank 0, we
* can NOT execute the code that modifies bank 0 timings from ROM, so
* we run it from cache.
*
* Bank 0 - Boot-Flash
* Bank 1 - NAND-Flash
* Bank 2 - ISA bus
* Bank 3 - Second Flash
* Bank 4 - USB controller
*/
.globl ext_bus_cntlr_init
ext_bus_cntlr_init:
/*
* We need the current boot up configuration to set correct
* timings into internal flash and external flash
*/
mfdcr r24,CPC0_PSR /* xxxx xxxx xxxx xxx? ?xxx xxxx xxxx xxxx
0 0 -> 8 bit external ROM
0 1 -> 16 bit internal ROM */
addi r4,0,2
srw r24,r24,r4 /* shift right r24 two positions */
andi. r24,r24,0x06000
/*
* All calculations are based on 33MHz EBC clock.
*
* First, create a "very slow" timing (~250ns) with burst mode enabled
* This is need for the external flash access
*/
lis r25,0x0800
/* 0000 1000 0xxx 0000 0000 0010 100x xxxx = 0x03800280 */
ori r25,r25,0x0280
/*
* Second, create a fast timing:
* 90ns first cycle - 3 clock access
* and 90ns burst cycle, plus 1 clock after the last access
* This is used for the internal access
*/
lis r26,0x8900
/* 1000 1001 0xxx 0000 0000 0010 100x xxxx */
ori r26,r26,0x0280
/*
* We can't change settings on CS# if we currently use them.
* -> load a few instructions into cache and run this code from cache
*/
mflr r4 /* save link register */
bl ..getAddr
..getAddr:
mflr r3 /* get address of ..getAddr */
mtlr r4 /* restore link register */
addi r4,0,14 /* set ctr to 10; used to prefetch */
mtctr r4 /* 10 cache lines to fit this function
in cache (gives us 8x10=80 instructions) */
..ebcloop:
icbt r0,r3 /* prefetch cache line for addr in r3 */
addi r3,r3,32 /* move to next cache line */
bdnz ..ebcloop /* continue for 10 cache lines */
/*
* Delay to ensure all accesses to ROM are complete before changing
* bank 0 timings. 200usec should be enough.
* 200,000,000 (cycles/sec) X .000200 (sec) = 0x9C40 cycles
*/
lis r3,0x0
ori r3,r3,0xA000 /* ensure 200usec have passed since reset */
mtctr r3
..spinlp:
bdnz ..spinlp /* spin loop */
/*-----------------------------------------------------------------------
* Memory Bank 0 (BOOT-ROM) initialization
* 0xFFEF00000....0xFFFFFFF
* We only have to change the timing. Mapping is ok by boot-strapping
*----------------------------------------------------------------------- */
li r4,PB1AP /* PB0AP=Peripheral Bank 0 Access Parameters */
mtdcr EBC0_CFGADDR,r4
mr r4,r26 /* assume internal fast flash is boot flash */
cmpwi r24,0x2000 /* assumption true? ... */
beq 1f /* ...yes! */
mr r4,r25 /* ...no, use the slow variant */
mr r25,r26 /* use this for the other flash */
1:
mtdcr EBC0_CFGDATA,r4 /* change timing now */
li r4,PB0CR /* PB0CR=Peripheral Bank 0 Control Register */
mtdcr EBC0_CFGADDR,r4
mfdcr r4,EBC0_CFGDATA
lis r3,0x0001
ori r3,r3,0x8000 /* allow reads and writes */
or r4,r4,r3
mtdcr EBC0_CFGDATA,r4
/*-----------------------------------------------------------------------
* Memory Bank 3 (Second-Flash) initialization
* 0xF0000000...0xF01FFFFF -> 2MB
*----------------------------------------------------------------------- */
li r4,PB3AP /* Peripheral Bank 1 Access Parameter */
mtdcr EBC0_CFGADDR,r4
mtdcr EBC0_CFGDATA,r2 /* change timing */
li r4,PB3CR /* Peripheral Bank 1 Configuration Registers */
mtdcr EBC0_CFGADDR,r4
lis r4,0xF003
ori r4,r4,0x8000
/*
* Consider boot configuration
*/
xori r24,r24,0x2000 /* invert current bus width */
or r4,r4,r24
mtdcr EBC0_CFGDATA,r4
/*-----------------------------------------------------------------------
* Memory Bank 1 (NAND-Flash) initialization
* 0x77D00000...0x77DFFFFF -> 1MB
* - the write/read pulse to the NAND can be as short as 25ns, bus the cycle time is always 50ns
* - the setup time is 0ns
* - the hold time is 15ns
* ->
* - TWT = 0
* - CSN = 0
* - OEN = 0
* - WBN = 0
* - WBF = 0
* - TH = 1
* ----> 2 clocks per cycle = 60ns cycle (30ns active, 30ns hold)
*----------------------------------------------------------------------- */
li r4,PB1AP /* Peripheral Bank 1 Access Parameter */
mtdcr EBC0_CFGADDR,r4
lis r4,0x0000
ori r4,r4,0x0200
mtdcr EBC0_CFGDATA,r4
li r4,PB1CR /* Peripheral Bank 1 Configuration Registers */
mtdcr EBC0_CFGADDR,r4
lis r4,0x77D1
ori r4,r4,0x8000
mtdcr EBC0_CFGDATA,r4
/* USB init (without acceleration) */
#ifndef CONFIG_ISP1161_PRESENT
li r4,PB4AP /* PB4AP=Peripheral Bank 4 Access Parameters */
mtdcr EBC0_CFGADDR,r4
lis r4,0x0180
ori r4,r4,0x5940
mtdcr EBC0_CFGDATA,r4
#endif
/*-----------------------------------------------------------------------
* Memory Bank 2 (ISA Access) initialization (plus memory bank 6 and 7)
* 0x78000000...0x7BFFFFFF -> 64 MB
* Wir arbeiten bei 33 MHz -> 30ns
*-----------------------------------------------------------------------
A7 (ppc notation) or A24 (standard notation) decides about
the type of access:
A7/A24=0 -> memory cycle
A7/ /A24=1 -> I/O cycle
*/
li r4,PB2AP /* PB2AP=Peripheral Bank 2 Access Parameters */
mtdcr EBC0_CFGADDR,r4
/*
We emulate an ISA access
1. Address active
2. wait 0 EBC clocks -> CSN=0
3. set CS#
4. wait 0 EBC clock -> OEN/WBN=0
5. set OE#/WE#
6. wait 4 clocks (ca. 90ns) and for Ready signal
7. hold for 4 clocks -> TH=4
*/
#if 1
/* faster access to isa-bus */
lis r4,0x0180
ori r4,r4,0x5940
#else
lis r4,0x0100
ori r4,r4,0x0340
#endif
mtdcr EBC0_CFGDATA,r4
#ifdef IDE_USES_ISA_EMULATION
li r25,PB5AP /* PB5AP=Peripheral Bank 5 Access Parameters */
mtdcr EBC0_CFGADDR,r25
mtdcr EBC0_CFGDATA,r4
#endif
li r25,PB6AP /* PB6AP=Peripheral Bank 6 Access Parameters */
mtdcr EBC0_CFGADDR,r25
mtdcr EBC0_CFGDATA,r4
li r25,PB7AP /* PB7AP=Peripheral Bank 7 Access Parameters */
mtdcr EBC0_CFGADDR,r25
mtdcr EBC0_CFGDATA,r4
li r25,PB2CR /* PB2CR=Peripheral Bank 2 Configuration Register */
mtdcr EBC0_CFGADDR,r25
lis r4,0x780B
ori r4,r4,0xA000
mtdcr EBC0_CFGDATA,r4
/*
* the other areas are only 1MiB in size
*/
lis r4,0x7401
ori r4,r4,0xA000
li r25,PB6CR /* PB6CR=Peripheral Bank 6 Configuration Register */
mtdcr EBC0_CFGADDR,r25
lis r4,0x7401
ori r4,r4,0xA000
mtdcr EBC0_CFGDATA,r4
li r25,PB7CR /* PB7CR=Peripheral Bank 7 Configuration Register */
mtdcr EBC0_CFGADDR,r25
lis r4,0x7411
ori r4,r4,0xA000
mtdcr EBC0_CFGDATA,r4
#ifndef CONFIG_ISP1161_PRESENT
li r25,PB4CR /* PB4CR=Peripheral Bank 4 Configuration Register */
mtdcr EBC0_CFGADDR,r25
lis r4,0x7421
ori r4,r4,0xA000
mtdcr EBC0_CFGDATA,r4
#endif
#ifdef IDE_USES_ISA_EMULATION
li r25,PB5CR /* PB5CR=Peripheral Bank 5 Configuration Register */
mtdcr EBC0_CFGADDR,r25
lis r4,0x0000
ori r4,r4,0x0000
mtdcr EBC0_CFGDATA,r4
#endif
/*-----------------------------------------------------------------------
* Memory bank 4: USB controller Philips ISP6111
* 0x77C00000 ... 0x77CFFFFF
*
* The chip is connected to:
* - CPU CS#4
* - CPU IRQ#2
* - CPU DMA 3
*
* Timing:
* - command to first data: 300ns. Software must ensure this timing!
* - Write pulse: 26ns
* - Read pulse: 33ns
* - read cycle time: 150ns
* - write cycle time: 140ns
*
* Note: All calculations are based on 33MHz EBC clock. One '#' or '_' is 30ns
*
* |- 300ns --|
* |---- 420ns ---|---- 420ns ---| cycle
* CS ############:###____#######:###____#######
* OE ############:####___#######:####___#######
* WE ############:####__########:####__########
*
* ----> 2 clocks RD/WR pulses: 60ns
* ----> CSN: 3 clock, 90ns
* ----> OEN: 1 clocks (read cycle)
* ----> WBN: 1 clocks (write cycle)
* ----> WBE: 2 clocks
* ----> TH: 7 clock, 210ns
* ----> TWT: 7 clocks
*----------------------------------------------------------------------- */
#ifdef CONFIG_ISP1161_PRESENT
li r4,PB4AP /* PB4AP=Peripheral Bank 4 Access Parameters */
mtdcr EBC0_CFGADDR,r4
lis r4,0x030D
ori r4,r4,0x5E80
mtdcr EBC0_CFGDATA,r4
li r4,PB4CR /* PB2CR=Peripheral Bank 4 Configuration Register */
mtdcr EBC0_CFGADDR,r4
lis r4,0x77C1
ori r4,r4,0xA000
mtdcr EBC0_CFGDATA,r4
#endif
#ifndef IDE_USES_ISA_EMULATION
/*-----------------------------------------------------------------------
* Memory Bank 5 used for IDE access
*
* Timings for IDE Interface
*
* SETUP / LENGTH / HOLD - cycles valid for 33.3 MHz clk -> 30ns cycle time
* 70 165 30 PIO-Mode 0, [ns]
* 3 6 1 [Cycles] ----> AP=0x040C0200
* 50 125 20 PIO-Mode 1, [ns]
* 2 5 1 [Cycles] ----> AP=0x03080200
* 30 100 15 PIO-Mode 2, [ns]
* 1 4 1 [Cycles] ----> AP=0x02040200
* 30 80 10 PIO-Mode 3, [ns]
* 1 3 1 [Cycles] ----> AP=0x01840200
* 25 70 10 PIO-Mode 4, [ns]
* 1 3 1 [Cycles] ----> AP=0x01840200
*
*----------------------------------------------------------------------- */
li r4,PB5AP
mtdcr EBC0_CFGADDR,r4
lis r4,0x040C
ori r4,r4,0x0200
mtdcr EBC0_CFGDATA,r4
li r4,PB5CR /* PB2CR=Peripheral Bank 2 Configuration Register */
mtdcr EBC0_CFGADDR,r4
lis r4,0x7A01
ori r4,r4,0xA000
mtdcr EBC0_CFGDATA,r4
#endif
/*
* External Peripheral Control Register
*/
li r4,EBC0_CFG
mtdcr EBC0_CFGADDR,r4
lis r4,0xB84E
ori r4,r4,0xF000
mtdcr EBC0_CFGDATA,r4
/*
* drive POST code
*/
lis r4,0x7900
ori r4,r4,0x0080
li r3,0x0001
stb r3,0(r4) /* 01 -> external bus controller is initialized */
nop /* pass2 DCR errata #8 */
blr