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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/powerpc/boot/opal.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/boot/opal.c')
-rw-r--r-- | arch/powerpc/boot/opal.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/arch/powerpc/boot/opal.c b/arch/powerpc/boot/opal.c new file mode 100644 index 000000000..b69818ce5 --- /dev/null +++ b/arch/powerpc/boot/opal.c @@ -0,0 +1,97 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2016 IBM Corporation. + */ + +#include "ops.h" +#include "stdio.h" +#include "io.h" +#include <libfdt.h> +#include "../include/asm/opal-api.h" + +/* Global OPAL struct used by opal-call.S */ +struct opal { + u64 base; + u64 entry; +} opal; + +static u32 opal_con_id; + +/* see opal-wrappers.S */ +int64_t opal_console_write(int64_t term_number, u64 *length, const u8 *buffer); +int64_t opal_console_read(int64_t term_number, uint64_t *length, u8 *buffer); +int64_t opal_console_write_buffer_space(uint64_t term_number, uint64_t *length); +int64_t opal_console_flush(uint64_t term_number); +int64_t opal_poll_events(uint64_t *outstanding_event_mask); + +void opal_kentry(unsigned long fdt_addr, void *vmlinux_addr); + +static int opal_con_open(void) +{ + /* + * When OPAL loads the boot kernel it stashes the OPAL base and entry + * address in r8 and r9 so the kernel can use the OPAL console + * before unflattening the devicetree. While executing the wrapper will + * probably trash r8 and r9 so this kentry hook restores them before + * entering the decompressed kernel. + */ + platform_ops.kentry = opal_kentry; + return 0; +} + +static void opal_con_putc(unsigned char c) +{ + int64_t rc; + uint64_t olen, len; + + do { + rc = opal_console_write_buffer_space(opal_con_id, &olen); + len = be64_to_cpu(olen); + if (rc) + return; + opal_poll_events(NULL); + } while (len < 1); + + + olen = cpu_to_be64(1); + opal_console_write(opal_con_id, &olen, &c); +} + +static void opal_con_close(void) +{ + opal_console_flush(opal_con_id); +} + +static void opal_init(void) +{ + void *opal_node; + + opal_node = finddevice("/ibm,opal"); + if (!opal_node) + return; + if (getprop(opal_node, "opal-base-address", &opal.base, sizeof(u64)) < 0) + return; + opal.base = be64_to_cpu(opal.base); + if (getprop(opal_node, "opal-entry-address", &opal.entry, sizeof(u64)) < 0) + return; + opal.entry = be64_to_cpu(opal.entry); +} + +int opal_console_init(void *devp, struct serial_console_data *scdp) +{ + opal_init(); + + if (devp) { + int n = getprop(devp, "reg", &opal_con_id, sizeof(u32)); + if (n != sizeof(u32)) + return -1; + opal_con_id = be32_to_cpu(opal_con_id); + } else + opal_con_id = 0; + + scdp->open = opal_con_open; + scdp->putc = opal_con_putc; + scdp->close = opal_con_close; + + return 0; +} |