From 12a05b3bcd85ff4aa930e7a1fb8795d5a6bfdf81 Mon Sep 17 00:00:00 2001 From: Sean Anderson Date: Tue, 22 Mar 2022 16:59:18 -0400 Subject: arm: smh: Add some file manipulation commands In order to add filesystem support, we will need to be able to seek and write files. Add the appropriate helper functions. Signed-off-by: Sean Anderson --- arch/arm/lib/semihosting.c | 67 ++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 56 insertions(+), 11 deletions(-) (limited to 'arch/arm/lib/semihosting.c') diff --git a/arch/arm/lib/semihosting.c b/arch/arm/lib/semihosting.c index 2943f7b82fb..d08003cef1e 100644 --- a/arch/arm/lib/semihosting.c +++ b/arch/arm/lib/semihosting.c @@ -1,15 +1,13 @@ // SPDX-License-Identifier: GPL-2.0+ /* + * Copyright (C) 2022 Sean Anderson * Copyright 2014 Broadcom Corporation */ /* - * Minimal semihosting implementation for reading files into memory. If more - * features like writing files or console output are required they can be - * added later. This code has been tested on arm64/aarch64 fastmodel only. - * An untested placeholder exists for armv7 architectures, but since they - * are commonly available in silicon now, fastmodel usage makes less sense - * for them. + * This code has been tested on arm64/aarch64 fastmodel only. An untested + * placeholder exists for armv7 architectures, but since they are commonly + * available in silicon now, fastmodel usage makes less sense for them. */ #include #include @@ -19,7 +17,9 @@ #define SYSOPEN 0x01 #define SYSCLOSE 0x02 +#define SYSWRITE 0x05 #define SYSREAD 0x06 +#define SYSSEEK 0x0A #define SYSFLEN 0x0C #define SYSERRNO 0x13 @@ -80,14 +80,22 @@ long smh_open(const char *fname, enum smh_open_mode mode) return fd; } +/** + * struct smg_rdwr_s - Arguments for read and write + * @fd: A file descriptor returned from smh_open() + * @memp: Pointer to a buffer of memory of at least @len bytes + * @len: The number of bytes to read or write + */ +struct smh_rdwr_s { + long fd; + void *memp; + size_t len; +}; + long smh_read(long fd, void *memp, size_t len) { long ret; - struct smh_read_s { - long fd; - void *memp; - size_t len; - } read; + struct smh_rdwr_s read; debug("%s: fd %ld, memp %p, len %zu\n", __func__, fd, memp, len); @@ -101,6 +109,24 @@ long smh_read(long fd, void *memp, size_t len) return len - ret; } +long smh_write(long fd, const void *memp, size_t len, ulong *written) +{ + long ret; + struct smh_rdwr_s write; + + debug("%s: fd %ld, memp %p, len %zu\n", __func__, fd, memp, len); + + write.fd = fd; + write.memp = (void *)memp; + write.len = len; + + ret = smh_trap(SYSWRITE, &write); + *written = len - ret; + if (ret) + return smh_errno(); + return 0; +} + long smh_close(long fd) { long ret; @@ -125,6 +151,25 @@ long smh_flen(long fd) return ret; } +long smh_seek(long fd, long pos) +{ + long ret; + struct smh_seek_s { + long fd; + long pos; + } seek; + + debug("%s: fd %ld pos %ld\n", __func__, fd, pos); + + seek.fd = fd; + seek.pos = pos; + + ret = smh_trap(SYSSEEK, &seek); + if (ret) + return smh_errno(); + return 0; +} + static int smh_load_file(const char * const name, ulong load_addr, ulong *end_addr) { -- cgit v1.2.3