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authorJonathan Neuschäfer <j.neuschaefer@gmx.net>2016-08-22 19:37:16 +0200
committerRonald G. Minnich <rminnich@gmail.com>2016-08-23 23:47:01 +0200
commit857e33e27f1feeec328ae8be5ad61ee51b75e4ec (patch)
treedd743b4fda0ac4c6f485e56a982fbc50932a4e42 /src/arch/riscv/sbi.S
parent3965a522c23ea50b1a861b89a8215a524caa35f7 (diff)
arch/riscv: Implement the SBI again
Not all SBI calls are implemented, but it's enough to see a couple dozen lines of Linux boot output. It should also be noted that the SBI is still in flux: https://groups.google.com/a/groups.riscv.org/forum/#!topic/sw-dev/6oNhlW0OFKM Change-Id: I80e4fe508336d6428ca7136bc388fbc3cda4f1e4 Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Reviewed-on: https://review.coreboot.org/16119 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/arch/riscv/sbi.S')
-rw-r--r--src/arch/riscv/sbi.S117
1 files changed, 117 insertions, 0 deletions
diff --git a/src/arch/riscv/sbi.S b/src/arch/riscv/sbi.S
new file mode 100644
index 0000000000..f4d5411879
--- /dev/null
+++ b/src/arch/riscv/sbi.S
@@ -0,0 +1,117 @@
+/*
+ * RISC-V supervisor binary interface (SBI) trampoline page
+ *
+ * Copyright 2016 Jonathan Neuschäfer <j.neuschaefer@gmx.net>
+ *
+ * This program 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; version 2 of
+ * the License.
+ *
+ * This program 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.
+ */
+
+#define __ASSEMBLY__
+#include <arch/encoding.h>
+#include <arch/sbi.h>
+
+.section ".text.sbi", "ax", %progbits
+
+/* align to a page boundary */
+.align RISCV_PGSHIFT
+
+.globl sbi_page
+sbi_page:
+
+ /*
+ * None of the SBI entry points is located in the first half of the
+ * page
+ */
+ .skip 0x800
+
+ /* -2048: size_t sbi_hart_id(void); */
+ li a7, SBI_ECALL_HART_ID
+ ecall
+ jr ra
+ .align 4
+
+ /* -2032: size_t sbi_num_harts(void); */
+ li a7, SBI_ECALL_NUM_HARTS
+ ecall
+ jr ra
+ .align 4
+
+ /* -2016: unsigned long sbi_query_memory(unsigned long id,
+ memory_block_info *p); */
+ li a7, SBI_ECALL_QUERY_MEMORY
+ ecall
+ jr ra
+ .align 4
+
+ /* -2000: int sbi_console_putchar(uint8_t ch); */
+ li a7, SBI_ECALL_CONSOLE_PUT
+ ecall
+ jr ra
+ .align 4
+
+ /* -1984: int sbi_console_getchar(void); */
+ li a0, -1 /* failure: Coreboot doesn't support console input */
+ jr ra
+ .align 4
+
+ /* -1968: Not allocated */
+ ebreak
+ .align 4
+
+ /* -1952: int sbi_send_ipi(size_t hart_id); */
+ ebreak
+ .align 4
+
+ /* -1936: int bool sbi_clear_ipi(void); */
+ ebreak
+ .align 4
+
+ /* -1920: unsigned long sbi_timebase(void); */
+ li a0, 1000000000 /* I have no idea. */
+ jr ra
+ .align 4
+
+ /* -1904: void sbi_shutdown(void); */
+ li a7, SBI_ECALL_SHUTDOWN
+ ecall
+ jr ra
+ .align 4
+
+ /* -1888: void sbi_set_timer(unsigned long long stime_value); */
+ li a7, SBI_ECALL_SET_TIMER
+ ecall
+ jr ra
+ .align 4
+
+ /* -1872: int sbi_mask_interrupt(int which); */
+ ebreak
+ .align 4
+
+ /* -1856: int sbi_unmask_interrupt(int which); */
+ ebreak
+ .align 4
+
+ /* -1840: void sbi_remote_sfence_vm(const uintptr_t* harts,
+ size_t asid); */
+ ebreak
+ .align 4
+
+ /* -1824: void sbi_remote_sfence_vm_range(const uintptr_t* harts,
+ size_t asid, uintptr_t start, uintptr_t size); */
+ ebreak
+ .align 4
+
+ /* -1808: void sbi_remote_fence_i(const uintptr_t* harts); */
+ ebreak
+ .align 4
+
+/* Fill the remainder of the page */
+.align RISCV_PGSHIFT