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-rw-r--r--qemu/roms/u-boot/board/cray/L1/init.S117
1 files changed, 117 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/board/cray/L1/init.S b/qemu/roms/u-boot/board/cray/L1/init.S
new file mode 100644
index 000000000..d4723c733
--- /dev/null
+++ b/qemu/roms/u-boot/board/cray/L1/init.S
@@ -0,0 +1,117 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0 IBM-pibs
+ */
+
+/*----------------------------------------------------------------------------- */
+/* Function: ext_bus_cntlr_init */
+/* Description: 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 - Flash and SRAM */
+/* Bank 1 - NVRAM/RTC */
+/* Bank 2 - Keyboard/Mouse controller */
+/* Bank 3 - IR controller */
+/* Bank 4 - not used */
+/* Bank 5 - not used */
+/* Bank 6 - not used */
+/* Bank 7 - FPGA registers */
+/*-----------------------------------------------------------------------------#include <config.h> */
+#include <asm/ppc4xx.h>
+
+#include <ppc_asm.tmpl>
+#include <ppc_defs.h>
+
+#include <asm/cache.h>
+#include <asm/mmu.h>
+
+/* CRAY - L1: only nominally a 'walnut', since ext.Bus.Cntlr is all empty */
+/* except for #1 which we use for DMA'ing to IOCA-like things, so the */
+/* control registers to set that up are determined by what we've */
+/* empirically discovered work there. */
+
+ .globl ext_bus_cntlr_init
+ext_bus_cntlr_init:
+ 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 instrctns) */
+..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 */
+ /*------------------------------------------------------------------- */
+ addis r3,0,0x0
+ ori r3,r3,0xA000 /* ensure 200usec have passed since reset */
+ mtctr r3
+..spinlp:
+ bdnz ..spinlp /* spin loop */
+
+
+ /*---------------------------------------------------------------------- */
+ /* Peripheral Bank 0 (Flash) initialization */
+ /*---------------------------------------------------------------------- */
+ /* 0x7F8FFE80 slowest boot */
+ addi r4,0,PB1AP
+ mtdcr EBC0_CFGADDR,r4
+ addis r4,0,0x9B01
+ ori r4,r4,0x5480
+ mtdcr EBC0_CFGDATA,r4
+
+ addi r4,0,PB0CR
+ mtdcr EBC0_CFGADDR,r4
+ addis r4,0,0xFFC5 /* BAS=0xFFC,BS=0x4(4MB),BU=0x3(R/W), */
+ ori r4,r4,0x8000 /* BW=0x0( 8 bits) */
+ mtdcr EBC0_CFGDATA,r4
+
+ blr
+
+ /*---------------------------------------------------------------------- */
+ /* Peripheral Bank 1 (NVRAM/RTC) initialization */
+ /* CRAY:the L1 has NOT this bank, it is tied to SV2/IOCA/etc/ instead */
+ /* and we do DMA on it. The ConfigurationRegister part is threfore */
+ /* almost arbitrary, except that our linux driver needs to know the */
+ /* address, but it can query, it.. */
+ /* */
+ /* The AccessParameter is CRITICAL, */
+ /* thouch, since it needs to agree with the electrical timings on the */
+ /* IOCA parallel interface. That value is: 0x0185,4380 */
+ /* BurstModeEnable BME=0 */
+ /* TransferWait TWT=3 */
+ /* ChipSelectOnTiming CSN=1 */
+ /* OutputEnableOnTimimg OEN=1 */
+ /* WriteByteEnableOnTiming WBN=1 */
+ /* WriteByteEnableOffTiming WBF=0 */
+ /* TransferHold TH=1 */
+ /* ReadyEnable RE=1 */
+ /* SampleOnReady SOR=1 */
+ /* ByteEnableMode BEM=0 */
+ /* ParityEnable PEN=0 */
+ /* all reserved bits=0 */
+ /*---------------------------------------------------------------------- */
+ /*---------------------------------------------------------------------- */
+ addi r4,0,PB1AP
+ mtdcr EBC0_CFGADDR,r4
+ addis r4,0,0x0185 /* hiword */
+ ori r4,r4,0x4380 /* loword */
+ mtdcr EBC0_CFGDATA,r4
+
+ addi r4,0,PB1CR
+ mtdcr EBC0_CFGADDR,r4
+ addis r4,0,0xF001 /* BAS=0xF00,BS=0x0(1MB),BU=0x3(R/W), */
+ ori r4,r4,0x8000 /* BW=0x0( 8 bits) */
+ mtdcr EBC0_CFGDATA,r4
+
+ blr