/* * 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 . */ #include #include #include #include #include #include #include #include #include #define GRUB_MACHINE_SERIAL_PORT GRUB_MACHINE_SERIAL_PORT0 #define GRUB_MACHINE_SERIAL_DIVISOR_115200 GRUB_MACHINE_SERIAL_PORT0_DIVISOR_115200 .set noreorder .set noat .set nomacro .global start,_start,__start start: _start: __start: bal serial_hw_init nop /* 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. */ /* We have only one bus (0). Function is 0. */ lui $t0, %hi(GRUB_MACHINE_PCI_CONF_CTRL_REG_ADDR) lui $t1, %hi(GRUB_MACHINE_PCI_CONFSPACE) lui $t3, %hi(GRUB_CS5536_PCIID) addiu $t3, $t3, %lo(GRUB_CS5536_PCIID) ori $t4, $zero, 1 lui $a0, %hi(no_cs5536) 1: andi $t4, $t4, ((1 << GRUB_PCI_NUM_DEVICES) - 1) beql $t4, $zero, fatal addiu $a0, $a0, %lo(no_cs5536) sw $t4, %lo(GRUB_MACHINE_PCI_CONF_CTRL_REG_ADDR) ($t0) lw $t2, (%lo(GRUB_MACHINE_PCI_CONFSPACE) + GRUB_PCI_REG_PCI_ID) ($t1) bnel $t2, $t3, 1b sll $t4, $t4, 1 bal message addiu $a0, $a0, %lo(cs5536_found) bal printhex move $a0, $t4 /* Initialise SMBus controller. */ /* 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) /* 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) /* Enable SMBus controller pins. */ lui $t0, %hi(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_GPIO) ori $t1, $zero, GRUB_GPIO_SMBUS_PINS sw $t1, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_GPIO + GRUB_GPIO_REG_OUT_EN) ($t0) sw $t1, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_GPIO + GRUB_GPIO_REG_OUT_AUX1) ($t0) sw $t1, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_GPIO + GRUB_GPIO_REG_IN_EN) ($t0) sw $t1, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_GPIO + GRUB_GPIO_REG_IN_AUX1) ($t0) lui $t0, %hi(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_SMBUS) /* Disable SMB. */ sb $zero, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL2) ($t0) /* Disable interrupts. */ sb $zero, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1) ($t0) /* Set as master. */ sb $zero, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_ADDR) ($t0) /* Launch SMBus controller at slowest speed possible. */ ori $t1, $zero, 0xff sb $t1, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL3) ($t0) sb $t1, %lo(GRUB_MACHINE_PCI_IO_BASE + GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL2) ($t0) /* Yeeloong has 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 . = start + 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) . = start + 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) . = start + 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) /* Same as similarly named C function but in asm since we need it early. */ /* In: none. Out: none. Clobbered: $t0, $t1, $a0. */ serial_hw_init: 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) /* 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 blt $t1, $zero, 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) sw $a0, (%lo(GRUB_MACHINE_PCI_CONFSPACE) + GRUB_CS5536_MSR_MAILBOX_ADDR) ($t0) sw $a1, (%lo(GRUB_MACHINE_PCI_CONFSPACE) + GRUB_CS5536_MSR_MAILBOX_DATA0) ($t0) jr $ra sw $a2, (%lo(GRUB_MACHINE_PCI_CONFSPACE) + GRUB_CS5536_MSR_MAILBOX_DATA1) ($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) lb $t0, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_STATUS + GRUB_MACHINE_PCI_IO_BASE) ($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, %hi(read_spd_fail) /* Send START. */ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) lb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) ($t0) ori $t1, $t1, GRUB_CS5536_SMB_REG_CTRL1_START bal smbus_wait sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) ($t0) /* Send device address. */ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE) sll $t1, $a1, 1 bal smbus_wait sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE) ($t0) /* Send ACK. */ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) lb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) ($t0) ori $t1, $t1, GRUB_CS5536_SMB_REG_CTRL1_ACK sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) ($t0) /* Send byte address. */ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE) bal smbus_wait sb $t2, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE) ($t0) /* Send START. */ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) lb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) ($t0) ori $t1, $t1, GRUB_CS5536_SMB_REG_CTRL1_START bal smbus_wait sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) ($t0) /* Send device address. */ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE) sll $t1, $a1, 1 ori $t1, $t1, 1 bal smbus_wait sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE) ($t0) /* Send STOP. */ lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) lb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) ($t0) ori $t1, $t1, GRUB_CS5536_SMB_REG_CTRL1_STOP bal smbus_wait sb $t1, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_CTRL1 + GRUB_MACHINE_PCI_IO_BASE) ($t0) lui $t0, %hi(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE) lb $v0, %lo(GRUB_CS5536_LBAR_SMBUS + GRUB_CS5536_SMB_REG_DATA + GRUB_MACHINE_PCI_IO_BASE) ($t0) jr $t3 andi $v0, $v0, 0xff read_spd_fail: jr $t3 ori $v0, $v0, 0x100 notification_string: .asciz "GRUB " no_cs5536: .asciz "No CS5536 found.\n\r" 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 */ .quad 0x0000010200000102 /* 8 */ .quad 0x0000060c00000000 /* 9 */ .quad 0x2323233f3f1f0200 /* a */ .quad 0x5f7f232323232323 /* b */ .quad 0x002a3c0615000000 /* c */ .quad 0x002a002a002a002a /* d */ .quad 0x002a002a002a002a /* e */ .quad 0x00b40020006d0004 /* f */ .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 */ .p2align 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 addiu $a2, $zero, -(1 + GRUB_ARCH_MACHINE_YEELOONG) cached_continue: