summaryrefslogtreecommitdiffstats
path: root/grub-core/boot/mips/loongson/fwstart.S
diff options
context:
space:
mode:
Diffstat (limited to 'grub-core/boot/mips/loongson/fwstart.S')
-rw-r--r--grub-core/boot/mips/loongson/fwstart.S756
1 files changed, 756 insertions, 0 deletions
diff --git a/grub-core/boot/mips/loongson/fwstart.S b/grub-core/boot/mips/loongson/fwstart.S
new file mode 100644
index 0000000..28c6346
--- /dev/null
+++ b/grub-core/boot/mips/loongson/fwstart.S
@@ -0,0 +1,756 @@
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2000,2001,2002,2003,2004,2005,2007,2008,2009,2010 Free Software Foundation, Inc.
+ *
+ * GRUB 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/mips/loongson/serial.h>
+#include <grub/mips/loongson/pci.h>
+#include <grub/mips/loongson.h>
+#include <grub/pci.h>
+#include <grub/machine/serial.h>
+#include <grub/machine/kernel.h>
+#include <grub/ns8250.h>
+#include <grub/cs5536.h>
+#include <grub/smbus.h>
+
+#ifndef FULOONG2F
+#include <grub/vgaregs.h>
+#define GRUB_SM712_REG_BASE 0x700000
+#define GRUB_SM712_PCIID 0x0712126f
+#endif
+
+#ifdef FULOONG2F
+#define GRUB_MACHINE_SERIAL_PORT GRUB_MACHINE_SERIAL_PORT2
+#define GRUB_MACHINE_SERIAL_DIVISOR_115200 GRUB_MACHINE_SERIAL_PORT2_DIVISOR_115200
+#else
+#define GRUB_MACHINE_SERIAL_PORT GRUB_MACHINE_SERIAL_PORT0
+#define GRUB_MACHINE_SERIAL_DIVISOR_115200 GRUB_MACHINE_SERIAL_PORT0_DIVISOR_115200
+#endif
+
+ .set noreorder
+ .set noat
+ .set nomacro
+ .set mips3
+
+ .global start,_start,__start
+start:
+_start:
+__start:
+ /* Put serial init as soon as possible. But on Fuloong2f serial is past
+ Geode, so on Fuloong2f we need Geode first.
+ */
+#ifndef FULOONG2F
+ bal serial_hw_init
+ nop
+#endif
+
+ /* Find CS5536 controller. */
+ /* $t4 chooses device in priority encoding. */
+ /* Resulting value is kept in GRUB_MACHINE_PCI_CONF_CTRL_REG.
+ This way we don't need to sacrifice a register for it. */
+retry_cs5536:
+ /* We have only one bus (0). Function is 0. */
+ lui $t0, %hi(GRUB_MACHINE_PCI_CONF_CTRL_REG_ADDR_2F)
+ lui $t1, %hi(GRUB_MACHINE_PCI_CONFSPACE_2F)
+ lui $t3, %hi(GRUB_CS5536_PCIID)
+ addiu $t3, $t3, %lo(GRUB_CS5536_PCIID)
+ ori $t4, $zero, 1
+1:
+ andi $t4, $t4, ((1 << GRUB_PCI_NUM_DEVICES_2F) - 1)
+ /* In case of failure try again. CS5536 may be slow to come up. */
+ beql $t4, $zero, retry_cs5536
+ nop
+ sw $t4, %lo(GRUB_MACHINE_PCI_CONF_CTRL_REG_ADDR_2F) ($t0)
+ lw $t2, (%lo(GRUB_MACHINE_PCI_CONFSPACE_2F) + GRUB_PCI_REG_PCI_ID) ($t1)
+ bnel $t2, $t3, 1b
+ sll $t4, $t4, 1
+
+#ifndef FULOONG2F
+ lui $a0, %hi(cs5536_found)
+ bal message
+ addiu $a0, $a0, %lo(cs5536_found)
+ bal printhex
+ move $a0, $t4
+#endif
+
+ lui $t0, %hi(GRUB_MACHINE_PCI_CONFSPACE_2F)
+ li $t1, GRUB_CS5536_MSR_MAILBOX_CONFIG_ENABLED
+ sw $t1, (%lo(GRUB_MACHINE_PCI_CONFSPACE_2F) + GRUB_CS5536_MSR_MAILBOX_CONFIG) ($t0)
+
+ /* Set GPIO LBAR. */
+ lui $a0, %hi(GRUB_CS5536_MSR_GPIO_BAR)
+ addiu $a0, $a0, %lo(GRUB_CS5536_MSR_GPIO_BAR)
+ ori $a1, $zero, GRUB_CS5536_LBAR_GPIO
+ /* Set mask to 0xf and enabled bit to 1. */
+ bal wrmsr
+ ori $a2, $zero, ((GRUB_CS5536_LBAR_MASK_MASK \
+ | GRUB_CS5536_LBAR_ENABLE) >> 32)
+
+ bal gpio_init
+ nop
+
+#ifdef FULOONG2F
+ bal serial_hw_init
+ nop
+#endif
+
+ /* Initialise SMBus controller. */
+ /* Set SMBUS LBAR. */
+ lui $a0, %hi(GRUB_CS5536_MSR_SMB_BAR)
+ addiu $a0, $a0, %lo(GRUB_CS5536_MSR_SMB_BAR)
+ ori $a1, $zero, GRUB_CS5536_LBAR_SMBUS
+ /* Set mask to 0xf and enabled bit to 1. */
+ bal wrmsr
+ ori $a2, $zero, ((GRUB_CS5536_LBAR_MASK_MASK \
+ | GRUB_CS5536_LBAR_ENABLE) >> 32)
+
+ lui $a0, %hi(smbus_enabled)
+ bal message
+ addiu $a0, $a0, %lo(smbus_enabled)
+
+ lui $t0, %hi(GRUB_MACHINE_PCI_IO_BASE_2F + GRUB_CS5536_LBAR_SMBUS)
+
+ /* Disable SMB. */
+ sb $zero, %lo(GRUB_MACHINE_PCI_IO_BASE_2F + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL2) ($t0)
+
+ /* Disable interrupts. */
+ sb $zero, %lo(GRUB_MACHINE_PCI_IO_BASE_2F + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1) ($t0)
+
+ /* Set as master. */
+ sb $zero, %lo(GRUB_MACHINE_PCI_IO_BASE_2F + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_ADDR) ($t0)
+
+ /* Launch SMBus controller at slowest speed possible. */
+ ori $t1, $zero, 0xff
+ sb $t1, %lo(GRUB_MACHINE_PCI_IO_BASE_2F + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL3) ($t0)
+ sb $t1, %lo(GRUB_MACHINE_PCI_IO_BASE_2F + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL2) ($t0)
+
+ /* Yeeloong and Fuloong2f have only one memory slot. */
+ /* Output first byte on serial for debugging. */
+ ori $a1, $zero, GRUB_SMB_RAM_START_ADDR
+ bal read_spd
+ move $a0, $zero
+ bal printhex
+ move $a0, $v0
+
+ bal read_spd
+ ori $a0, $zero, GRUB_SMBUS_SPD_MEMORY_TYPE_ADDR
+ ori $t0, $zero, GRUB_SMBUS_SPD_MEMORY_TYPE_DDR2
+ lui $a0, %hi(unimplemented_memory_type)
+ bne $t0, $v0, fatal
+ addiu $a0, $a0, %lo(unimplemented_memory_type)
+
+ /* And here is our goal: DDR2 controller initialisation. */
+ lui $t0, %hi(GRUB_CPU_LOONGSON_CORECFG)
+ ld $t1, %lo(GRUB_CPU_LOONGSON_CORECFG) ($t0)
+ /* Use addiu for sign-extension. */
+ addiu $t2, $zero, ~(GRUB_CPU_LOONGSON_CORECFG_DISABLE_DDR2_SPACE|GRUB_CPU_LOONGSON_CORECFG_BUFFER_CPU)
+ and $t1, $t1, $t2
+ sd $t1, %lo (GRUB_CPU_LOONGSON_CORECFG) ($t0)
+
+ b continue
+
+ .org GRUB_CPU_LOONGSON_FLASH_TLB_REFILL - GRUB_CPU_LOONGSON_FLASH_START
+tlb_refill:
+ mfc0 $s1, GRUB_CPU_LOONGSON_COP0_EPC
+ mfc0 $s2, GRUB_CPU_LOONGSON_COP0_BADVADDR
+ move $s3, $ra
+ lui $a0, %hi(epc)
+ bal message
+ addiu $a0, $a0, %lo(epc)
+
+ bal printhex
+ move $a0, $s1
+
+ lui $a0, %hi(badvaddr)
+ bal message
+ addiu $a0, $a0, %lo(badvaddr)
+
+ bal printhex
+ move $a0, $s2
+
+ lui $a0, %hi(return_msg)
+ bal message
+ addiu $a0, $a0, %lo(return_msg)
+
+ bal printhex
+ move $a0, $s3
+
+ lui $a0, %hi(newline)
+ bal message
+ addiu $a0, $a0, %lo(newline)
+
+ lui $a0, %hi(unhandled_tlb_refill)
+ b fatal
+ addiu $a0, $a0, %lo(unhandled_tlb_refill)
+
+ .org GRUB_CPU_LOONGSON_FLASH_CACHE_ERROR - GRUB_CPU_LOONGSON_FLASH_START
+cache_error:
+ lui $a0, %hi(unhandled_cache_error)
+ b fatal
+ addiu $a0, $a0, %lo(unhandled_cache_error)
+
+ .org GRUB_CPU_LOONGSON_FLASH_OTHER_EXCEPTION - GRUB_CPU_LOONGSON_FLASH_START
+other_exception:
+ mfc0 $s0, GRUB_CPU_LOONGSON_COP0_CAUSE
+ mfc0 $s1, GRUB_CPU_LOONGSON_COP0_EPC
+ mfc0 $s2, GRUB_CPU_LOONGSON_COP0_BADVADDR
+ lui $a0, %hi(cause)
+ bal message
+ addiu $a0, $a0, %lo(cause)
+
+ bal printhex
+ move $a0, $s0
+
+ lui $a0, %hi(epc)
+ bal message
+ addiu $a0, $a0, %lo(epc)
+
+ bal printhex
+ move $a0, $s1
+
+ lui $a0, %hi(badvaddr)
+ bal message
+ addiu $a0, $a0, %lo(badvaddr)
+
+ bal printhex
+ move $a0, $s2
+
+ lui $a0, %hi(newline)
+ bal message
+ addiu $a0, $a0, %lo(newline)
+
+ lui $a0, %hi(unhandled_exception)
+ b fatal
+ addiu $a0, $a0, %lo(unhandled_exception)
+
+gpio_init:
+ lui $t0, %hi(GRUB_MACHINE_PCI_IO_BASE_2F + GRUB_CS5536_LBAR_GPIO)
+ addiu $t0, $t0, %lo(GRUB_MACHINE_PCI_IO_BASE_2F + GRUB_CS5536_LBAR_GPIO)
+ lui $t1, %hi (gpio_dump)
+ addiu $t1, $t1, %lo (gpio_dump)
+
+1:
+ lw $t2, 0($t1)
+ sw $t2, 0($t0)
+ addiu $t0, $t0, 4
+ addiu $t1, $t1, 4
+ lui $t2, %hi (gpio_dump_end)
+ addiu $t2, $t2, %lo (gpio_dump_end)
+ bne $t1, $t2, 1b
+ nop
+ jr $ra
+ nop
+
+ /* Same as similarly named C function but in asm since
+ we need it early. */
+ /* In: none. Out: none. Clobbered: $t0, $t1, $t2, $a0, $a1, $a2. */
+serial_hw_init:
+ move $t2, $ra
+#ifdef FULOONG2F
+ lui $a0, %hi(GRUB_CS5536_MSR_DIVIL_LEG_IO)
+ addiu $a0, $a0, %lo(GRUB_CS5536_MSR_DIVIL_LEG_IO)
+ lui $a1, %hi (GRUB_CS5536_MSR_DIVIL_LEG_IO_UART2_COM3 \
+ | GRUB_CS5536_MSR_DIVIL_LEG_IO_F_REMAP \
+ | GRUB_CS5536_MSR_DIVIL_LEG_IO_MODE_X86 \
+ | GRUB_CS5536_MSR_DIVIL_LEG_IO_UART1_COM1)
+ ori $a1, $a1, (GRUB_CS5536_MSR_DIVIL_LEG_IO_RTC_ENABLE0 \
+ | GRUB_CS5536_MSR_DIVIL_LEG_IO_RTC_ENABLE1)
+ bal wrmsr
+ move $a2, $zero
+
+ lui $a0, %hi(GRUB_CS5536_MSR_DIVIL_UART1_CONF)
+ addiu $a0, $a0, %lo(GRUB_CS5536_MSR_DIVIL_UART1_CONF)
+ li $a1, 2
+ bal wrmsr
+ move $a2, $zero
+
+ lui $a0, %hi(GRUB_CS5536_MSR_DIVIL_UART2_CONF)
+ addiu $a0, $a0, %lo(GRUB_CS5536_MSR_DIVIL_UART2_CONF)
+ li $a1, 2
+ bal wrmsr
+ move $a2, $zero
+#endif
+
+ lui $t0, %hi (GRUB_MACHINE_SERIAL_PORT)
+
+ /* Turn off the interrupt. */
+ sb $zero, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_IER)($t0)
+
+ /* Set DLAB. */
+ ori $t1, $zero, UART_DLAB
+ sb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_LCR)($t0)
+
+ /* Set the baud rate 115200. */
+ ori $t1, $zero, GRUB_MACHINE_SERIAL_DIVISOR_115200
+ sb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_DLL)($t0)
+ sb $zero, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_DLH)($t0)
+
+ /* Set the line status. */
+ ori $t1, $zero, (UART_NO_PARITY | UART_8BITS_WORD | UART_1_STOP_BIT)
+ sb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_LCR)($t0)
+
+ /* Enable the FIFO. */
+ ori $t1, $zero, UART_ENABLE_FIFO_TRIGGER1
+ sb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_FCR)($t0)
+
+ /* Turn on DTR and RTS. */
+ ori $t1, $zero, UART_ENABLE_DTRRTS
+ sb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_MCR)($t0)
+
+ /* Let message return to original caller. */
+ lui $a0, %hi(notification_string)
+ addiu $a0, $a0, %lo(notification_string)
+ move $ra, $t2
+
+ /* Print message on serial console. */
+ /* In: $a0 = asciiz message. Out: none. Clobbered: $t0, $t1, $a0. */
+message:
+ lui $t0, %hi (GRUB_MACHINE_SERIAL_PORT)
+1:
+ lb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_LSR)($t0)
+ andi $t1, $t1, UART_EMPTY_TRANSMITTER
+ beq $t1, $zero, 1b
+ nop
+ lb $t1, 0($a0)
+ sb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_TX)($t0)
+ bne $t1, $zero, 1b
+ addiu $a0, $a0, 1
+ jr $ra
+ nop
+
+ /* Print 32-bit hexadecimal on serial.
+ In: $a0. Out: None. Clobbered: $a0, $t0, $t1, $t2
+ */
+printhex:
+ lui $t0, %hi (GRUB_MACHINE_SERIAL_PORT)
+ ori $t2, $zero, 8
+1:
+ lb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_LSR)($t0)
+ andi $t1, $t1, UART_EMPTY_TRANSMITTER
+ beq $t1, $zero, 1b
+ nop
+ srl $t1, $a0, 28
+ addiu $t1, $t1, -10
+ bltz $t1, 2f
+ sll $a0, $a0, 4
+ addiu $t1, $t1, 'A'-10-'0'
+2: addiu $t1, $t1, '0'+10
+ sb $t1, (%lo (GRUB_MACHINE_SERIAL_PORT) + UART_TX)($t0)
+ addiu $t2, $t2, -1
+ bne $t2, $zero, 1b
+ nop
+ jr $ra
+ nop
+
+fatal:
+ bal message
+ nop
+self:
+ b self
+ nop
+
+ /* Write CS5536 MSR.
+ In: $a0 address, $a1 lower word, $a2 upper word.
+ Out: None
+ Clobbered: $t0
+ */
+wrmsr:
+ lui $t0, %hi(GRUB_MACHINE_PCI_CONFSPACE_2F)
+ sw $a0, (%lo(GRUB_MACHINE_PCI_CONFSPACE_2F) + GRUB_CS5536_MSR_MAILBOX_ADDR) ($t0)
+ sw $a1, (%lo(GRUB_MACHINE_PCI_CONFSPACE_2F) + GRUB_CS5536_MSR_MAILBOX_DATA0) ($t0)
+ jr $ra
+ sw $a2, (%lo(GRUB_MACHINE_PCI_CONFSPACE_2F) + GRUB_CS5536_MSR_MAILBOX_DATA1) ($t0)
+
+ /* Wait for SMBus data or empty transmitter. */
+ /* In: $a0 = exception handler. Out: none. Clobbered: $t0, $t1 */
+smbus_wait:
+1:
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_STATUS + GRUB_MACHINE_PCI_IO_BASE_2F)
+ lb $t0, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_STATUS + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+ andi $t1, $t0, GRUB_CS5536_SMB_REG_STATUS_SDAST
+ bne $t1, $zero, return
+ nop
+ andi $t1, $t0, (GRUB_CS5536_SMB_REG_STATUS_BER | GRUB_CS5536_SMB_REG_STATUS_NACK)
+ beq $t1, $zero, 1b
+ nop
+ jr $a0
+ nop
+return:
+ jr $ra
+ nop
+
+ /* Read SPD byte. In: $a0 byte, $a1 device. Out: $v0 read byte (0x100 on failure).
+ Clobbered: $t0, $t1, $t2, $t3, $a0. */
+read_spd:
+ move $t2, $a0
+ move $t3, $ra
+ lui $a0, %hi(read_spd_fail)
+ addiu $a0, $a0, %lo(read_spd_fail)
+
+ /* Send START. */
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F)
+ lb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+ ori $t1, $t1, GRUB_CS5536_SMB_REG_CTRL1_START
+ bal smbus_wait
+ sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+
+ /* Send device address. */
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE_2F)
+ sll $t1, $a1, 1
+ bal smbus_wait
+ sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+
+ /* Send ACK. */
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F)
+ lb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+ ori $t1, $t1, GRUB_CS5536_SMB_REG_CTRL1_ACK
+ sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+
+ /* Send byte address. */
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE_2F)
+ bal smbus_wait
+ sb $t2, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+
+ /* Send START. */
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F)
+ lb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+ ori $t1, $t1, GRUB_CS5536_SMB_REG_CTRL1_START
+ bal smbus_wait
+ sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+
+ /* Send device address. */
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE_2F)
+ sll $t1, $a1, 1
+ ori $t1, $t1, 1
+ bal smbus_wait
+ sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+
+ /* Send STOP. */
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F)
+ lb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+ ori $t1, $t1, GRUB_CS5536_SMB_REG_CTRL1_STOP
+ bal smbus_wait
+ sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+
+ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE_2F)
+ lb $v0, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE_2F) ($t0)
+ jr $t3
+ andi $v0, $v0, 0xff
+read_spd_fail:
+ jr $t3
+ ori $v0, $v0, 0x100
+
+notification_string: .asciz "GRUB "
+cs5536_found: .asciz "CS5536 at "
+sm_failed: .asciz "SM transaction failed.\n\r"
+unhandled_tlb_refill: .asciz "Unhandled TLB refill.\n\r"
+unhandled_cache_error: .asciz "Unhandled cache error.\n\r"
+unhandled_exception: .asciz "Unhandled exception.\n\r"
+smbus_enabled: .asciz "SMBus controller enabled.\n\r"
+unimplemented_memory_type: .asciz "non-DDR2 memory isn't supported.\n\r"
+no_cas_latency: .asciz "Couldn't determine CAS latency.\n\r"
+cause: .asciz "Cause: "
+epc: .asciz "\n\rEPC: "
+badvaddr: .asciz "\n\rBadVaddr: "
+newline: .asciz "\n\r"
+return_msg: .asciz "\n\rReturn address: "
+caches_enabled: .asciz "Caches enabled\n\r"
+
+ .p2align 3
+
+regdump:
+ .quad 0x0100010000000101 /* 0 */
+ .quad 0x0100010100000000 /* 2 */
+ .quad 0x0101000001000000 /* 3 */
+ .quad 0x0100020200010101 /* 4 */
+ .quad 0x0a04030603050203 /* 6 */
+ .quad 0x0f0e040000010a0b /* 7 */
+#ifdef FULOONG2F
+ .quad 0x0000000100000001 /* 8 */
+#else
+ .quad 0x0000010200000102 /* 8 */
+#endif
+ .quad 0x0000060c00000000 /* 9 */
+ .quad 0x2323233f3f1f0200 /* a */
+ .quad 0x5f7f232323232323 /* b */
+ .quad 0x002a3c0615000000 /* c */
+ .quad 0x002a002a002a002a /* d */
+ .quad 0x002a002a002a002a /* e */
+#ifdef FULOONG2F
+ .quad 0x00b40020005b0004 /* f */
+#else
+ .quad 0x00b40020006d0004 /* f */
+#endif
+ .quad 0x070007ff00000087 /* 10 */
+ .quad 0x000000000016101f /* 11 */
+ .quad 0x001c000000000000 /* 12 */
+ .quad 0x28e1000200c8006b /* 13 */
+ .quad 0x0000204200c8002f /* 14 */
+ .quad 0x0000000000030d40 /* 15 */
+ .quad 0 /* 16 */
+ .quad 0 /* 17 */
+ .quad 0 /* 18 */
+ .quad 0 /* 19 */
+ .quad 0 /* 1a */
+ .quad 0 /* 1b */
+ .quad 0 /* 1c */
+
+/* Dump of GPIO connections. FIXME: Remove useless and macroify. */
+gpio_dump:
+#ifdef FULOONG2F
+ .long 0xffff0000, 0x2eefd110, 0xffff0000, 0xffff0000
+ .long 0x2eefd110, 0xffff0000, 0x1000efff, 0xefff1000
+ .long 0x3df3c20c, 0xffff0000, 0xffff0000, 0xffff0000
+ .long 0x7df3820c, 0x3df3c20c, 0xffff0000, 0x00000000
+ .long 0xffff0000, 0xffff0000, 0x3de3c21c, 0x3d83c27c
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0xffff0000, 0xffff0000, 0xffff0000, 0xffff0000
+ .long 0xffff0000, 0xffff0000, 0x0000ffff, 0xffff0000
+ .long 0xefff1000, 0xffff0000, 0xffff0000, 0xffff0000
+ .long 0xefff1000, 0xefff1000, 0xffff0000, 0x00000000
+ .long 0xffff0000, 0xffff0000, 0xefff1000, 0xefff1000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+#else
+ .long 0xffff0000, 0x2ffdd002, 0xffff0000, 0xffff0000
+ .long 0x2fffd000, 0xffff0000, 0x1000efff, 0xefff1000
+ .long 0x3ffbc004, 0xffff0000, 0xffff0000, 0xffff0000
+ .long 0x3ffbc004, 0x3ffbc004, 0xffff0000, 0x00000000
+ .long 0xffff0000, 0xffff0000, 0x3ffbc004, 0x3f9bc064
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0xffff0000, 0xffff0000, 0xffff0000, 0xffff0000
+ .long 0xffff0000, 0xffff0000, 0x0000ffff, 0xffff0000
+ .long 0xefff1000, 0xffff0000, 0xffff0000, 0xffff0000
+ .long 0xefff1000, 0xefff1000, 0xffff0000, 0x00000000
+ .long 0xffff0000, 0xffff0000, 0xefff1000, 0xffff0000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0x00000000, 0x00000000, 0x00000000, 0x00000000
+ .long 0x00000000, 0x50000000, 0x00000000, 0x00000000
+#endif
+gpio_dump_end:
+
+ .p2align 3
+
+write_dumpreg:
+ ld $t2, 0($t6)
+ sd $t2, 0($t4)
+ addiu $t4, $t4, GRUB_CPU_LOONGSON_DDR2_REG_STEP
+ jr $ra
+ addiu $t6, $t6, GRUB_CPU_LOONGSON_DDR2_REG_SIZE
+
+continue:
+ lui $t4, %hi(GRUB_CPU_LOONGSON_DDR2_BASE)
+ addiu $t4, $t4, %lo(GRUB_CPU_LOONGSON_DDR2_BASE)
+ lui $t6, %hi(regdump)
+
+ /* 0 */
+ bal write_dumpreg
+ addiu $t6, $t6, %lo(regdump)
+
+ /* 1 */
+ ori $a1, $a1, GRUB_SMB_RAM_START_ADDR
+ move $t8, $zero
+ lui $t5, 0x0001
+ bal read_spd
+ ori $a0, $zero, GRUB_SMBUS_SPD_MEMORY_NUM_BANKS_ADDR
+ ori $t7, $zero, 8
+ bne $v0, $t7, 1f
+ ori $t5, $t5, 0x0001
+ ori $t8, $t8, GRUB_CPU_LOONGSON_DDR2_REG1_HI_8BANKS
+1:
+ dsll $t8, $t8, 32
+ or $t5, $t5, $t8
+ sd $t5, 0 ($t4)
+ addiu $t4, $t4, GRUB_CPU_LOONGSON_DDR2_REG_STEP
+
+ /* 2 */
+ bal write_dumpreg
+ nop
+
+ /* 3 */
+ bal write_dumpreg
+ nop
+
+ /* 4 */
+ bal write_dumpreg
+ nop
+
+ /* 5 */
+ /* FIXME: figure termination resistance. */
+ ori $t5, $zero, 0x2
+ bal read_spd
+ ori $a0, $zero, GRUB_SMBUS_SPD_MEMORY_NUM_ROWS_ADDR
+ /* $v0 = 15 - $v0. */
+ xori $v0, $v0, 0xf
+ andi $v0, $v0, 0x7
+ sll $v0, $v0, 8
+ or $t5, $t5, $v0
+
+ /* Find the fastest supported CAS latency. */
+ bal read_spd
+ ori $a0, $zero, GRUB_SMBUS_SPD_MEMORY_CAS_LATENCY_ADDR
+ ori $t0, $zero, GRUB_SMBUS_SPD_MEMORY_CAS_LATENCY_MIN_VALUE
+ ori $t1, $zero, (1 << GRUB_SMBUS_SPD_MEMORY_CAS_LATENCY_MIN_VALUE)
+2:
+ and $t2, $t1, $v0
+ bne $t2, $zero, 1f
+ ori $t3, $zero, 8
+ lui $a0, %hi(no_cas_latency)
+ beq $t0, $t3, fatal
+ addiu $a0, $a0, %lo(no_cas_latency)
+ addiu $t0, $t0, 1
+ b 2b
+ sll $t1, $t1, 1
+1:
+ sll $t0, $t0, 16
+ or $t5, $t5, $t0
+
+ bal read_spd
+ ori $a0, $zero, GRUB_SMBUS_SPD_MEMORY_NUM_COLUMNS_ADDR
+ /* $v0 = 15 - ($v0 + 1) = 14 - $v0. */
+ addiu $v0, $v0, 1
+ xori $v0, $v0, 0xf
+ andi $v0, $v0, 0x7
+ sll $v0, 24
+ or $t5, $t5, $v0
+ sd $t5, 0 ($t4)
+
+ addiu $t4, $t4, GRUB_CPU_LOONGSON_DDR2_REG_STEP
+
+ ori $t7, $zero, 0x16
+
+1:
+ ld $t2, 0($t6)
+ sd $t2, 0($t4)
+ addiu $t4, $t4, GRUB_CPU_LOONGSON_DDR2_REG_STEP
+ addiu $t7, $t7, -1
+ bne $t7, $zero, 1b
+ addiu $t6, $t6, GRUB_CPU_LOONGSON_DDR2_REG_SIZE
+
+ lui $t4, %hi(GRUB_CPU_LOONGSON_DDR2_BASE)
+ ld $t5, (%lo(GRUB_CPU_LOONGSON_DDR2_BASE) + 0x30) ($t4)
+ ori $t0, $zero, 1
+ dsll $t0, $t0, 40
+ or $t5, $t5, $t0
+ sd $t5, (%lo(GRUB_CPU_LOONGSON_DDR2_BASE) + 0x30) ($t4)
+
+ /* Desactivate DDR2 registers. */
+ lui $t0, %hi (GRUB_CPU_LOONGSON_CORECFG)
+ ld $t1, %lo (GRUB_CPU_LOONGSON_CORECFG) ($t0)
+ ori $t1, $t1, GRUB_CPU_LOONGSON_CORECFG_DISABLE_DDR2_SPACE
+ sd $t1, %lo (GRUB_CPU_LOONGSON_CORECFG) ($t0)
+
+ /* Enable cache. */
+ mfc0 $t0, GRUB_CPU_LOONGSON_COP0_CACHE_CONFIG
+ addiu $t1, $zero, ~GRUB_CPU_LOONGSON_CACHE_TYPE_MASK
+ and $t0, $t1, $t1
+ /* Set line size to 32 bytes and disabled cache. */
+ ori $t0, $t0, (GRUB_CPU_LOONGSON_COP0_CACHE_CONFIG_ILINESIZE \
+ | GRUB_CPU_LOONGSON_COP0_CACHE_CONFIG_DLINESIZE \
+ | GRUB_CPU_LOONGSON_CACHE_ACCELERATED)
+ mtc0 $t0, GRUB_CPU_LOONGSON_COP0_CACHE_CONFIG
+
+ /* Invalidate all I-cache entries. */
+ srl $t1, $t0, GRUB_CPU_LOONGSON_COP0_CACHE_ISIZE_SHIFT
+ andi $t1, $t1, GRUB_CPU_LOONGSON_COP0_CACHE_SIZE_MASK
+ ori $t2, $zero, (1 << (GRUB_CPU_LOONGSON_COP0_CACHE_SIZE_OFFSET \
+ - GRUB_CPU_LOONGSON_CACHE_LINE_SIZE_LOG_BIG \
+ - GRUB_CPU_LOONGSON_I_CACHE_LOG_WAYS))
+ sll $t1, $t2, $t1
+ lui $t2, 0x8000
+
+1:
+ cache GRUB_CPU_LOONGSON_COP0_I_INDEX_INVALIDATE, 0($t2)
+ addiu $t1, $t1, -1
+ bne $t1, $zero, 1b
+ addiu $t2, $t2, (1 << GRUB_CPU_LOONGSON_COP0_I_INDEX_BIT_OFFSET)
+
+ /* Invalidate all D-cache entries. */
+ srl $t1, $t0, GRUB_CPU_LOONGSON_COP0_CACHE_DSIZE_SHIFT
+ andi $t1, $t1, GRUB_CPU_LOONGSON_COP0_CACHE_SIZE_MASK
+ ori $t2, $zero, (1 << (GRUB_CPU_LOONGSON_COP0_CACHE_SIZE_OFFSET \
+ - GRUB_CPU_LOONGSON_CACHE_LINE_SIZE_LOG_BIG \
+ - GRUB_CPU_LOONGSON_D_CACHE_LOG_WAYS))
+ sll $t1, $t2, $t1
+ lui $t2, 0x8000
+ mtc0 $zero, GRUB_CPU_LOONGSON_COP0_CACHE_TAGLO
+ mtc0 $zero, GRUB_CPU_LOONGSON_COP0_CACHE_TAGHI
+1:
+ /* All four ways. */
+ cache GRUB_CPU_LOONGSON_COP0_D_INDEX_TAG_STORE, 0($t2)
+ cache GRUB_CPU_LOONGSON_COP0_D_INDEX_TAG_STORE, 1($t2)
+ cache GRUB_CPU_LOONGSON_COP0_D_INDEX_TAG_STORE, 2($t2)
+ cache GRUB_CPU_LOONGSON_COP0_D_INDEX_TAG_STORE, 3($t2)
+ addiu $t1, $t1, -1
+ bne $t1, $zero, 1b
+ addiu $t2, $t2, (1 << GRUB_CPU_LOONGSON_COP0_D_INDEX_BIT_OFFSET)
+
+ /* Invalidate all S-cache entries. */
+ ori $t1, $zero, (1 << (GRUB_CPU_LOONGSON_SECONDARY_CACHE_LOG_SIZE \
+ - GRUB_CPU_LOONGSON_CACHE_LINE_SIZE_LOG_BIG \
+ - GRUB_CPU_LOONGSON_S_CACHE_LOG_WAYS))
+ lui $t2, 0x8000
+ mtc0 $zero, GRUB_CPU_LOONGSON_COP0_CACHE_TAGLO
+ mtc0 $zero, GRUB_CPU_LOONGSON_COP0_CACHE_TAGHI
+1:
+ /* All four ways. */
+ cache GRUB_CPU_LOONGSON_COP0_S_INDEX_TAG_STORE, 0($t2)
+ cache GRUB_CPU_LOONGSON_COP0_S_INDEX_TAG_STORE, 1($t2)
+ cache GRUB_CPU_LOONGSON_COP0_S_INDEX_TAG_STORE, 2($t2)
+ cache GRUB_CPU_LOONGSON_COP0_S_INDEX_TAG_STORE, 3($t2)
+ addiu $t1, $t1, -1
+ bne $t1, $zero, 1b
+ addiu $t2, $t2, (1 << GRUB_CPU_LOONGSON_COP0_D_INDEX_BIT_OFFSET)
+
+ /* Finally enable cache. */
+ mfc0 $t0, GRUB_CPU_LOONGSON_COP0_CACHE_CONFIG
+ addiu $t1, $zero, ~GRUB_CPU_LOONGSON_CACHE_TYPE_MASK
+ and $t0, $t1, $t1
+ ori $t0, $t0, GRUB_CPU_LOONGSON_CACHE_CACHED
+ mtc0 $t0, GRUB_CPU_LOONGSON_COP0_CACHE_CONFIG
+
+ lui $a0, %hi(caches_enabled)
+ bal message
+ addiu $a0, $a0, %lo(caches_enabled)
+
+ /* Set ROM delay cycles to 1. */
+ lui $t0, %hi(GRUB_CPU_LOONGSON_LIOCFG)
+ lw $t1, %lo(GRUB_CPU_LOONGSON_LIOCFG) ($t0)
+ addiu $t2, $zero, ~(GRUB_CPU_LOONGSON_ROM_DELAY_MASK \
+ << GRUB_CPU_LOONGSON_ROM_DELAY_OFFSET)
+ and $t1, $t1, $t2
+ ori $t1, $t1, (1 << GRUB_CPU_LOONGSON_ROM_DELAY_OFFSET)
+ sw $t1, %lo(GRUB_CPU_LOONGSON_LIOCFG) ($t0)
+
+ addiu $a0, $zero, -1
+ addiu $a1, $zero, -1
+
+ /* Take advantage of cache. */
+ lui $t0, %hi(cached_continue - 0x20000000)
+ addiu $t0, $t0, %lo(cached_continue - 0x20000000)
+ jr $t0
+#ifdef FULOONG2F
+ addiu $a2, $zero, -(1 + GRUB_ARCH_MACHINE_FULOONG2F)
+#else
+ addiu $a2, $zero, -(1 + GRUB_ARCH_MACHINE_YEELOONG)
+#endif
+
+cached_continue: