98 lines
2.2 KiB
C
98 lines
2.2 KiB
C
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// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Copyright (c) 2016 IBM Corporation.
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*/
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#include "ops.h"
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#include "stdio.h"
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#include "io.h"
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#include <libfdt.h>
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#include "../include/asm/opal-api.h"
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/* Global OPAL struct used by opal-call.S */
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struct opal {
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u64 base;
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u64 entry;
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} opal;
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static u32 opal_con_id;
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/* see opal-wrappers.S */
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int64_t opal_console_write(int64_t term_number, u64 *length, const u8 *buffer);
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int64_t opal_console_read(int64_t term_number, uint64_t *length, u8 *buffer);
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int64_t opal_console_write_buffer_space(uint64_t term_number, uint64_t *length);
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int64_t opal_console_flush(uint64_t term_number);
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int64_t opal_poll_events(uint64_t *outstanding_event_mask);
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void opal_kentry(unsigned long fdt_addr, void *vmlinux_addr);
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static int opal_con_open(void)
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{
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/*
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* When OPAL loads the boot kernel it stashes the OPAL base and entry
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* address in r8 and r9 so the kernel can use the OPAL console
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* before unflattening the devicetree. While executing the wrapper will
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* probably trash r8 and r9 so this kentry hook restores them before
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* entering the decompressed kernel.
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*/
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platform_ops.kentry = opal_kentry;
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return 0;
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}
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static void opal_con_putc(unsigned char c)
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{
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int64_t rc;
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uint64_t olen, len;
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do {
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rc = opal_console_write_buffer_space(opal_con_id, &olen);
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len = be64_to_cpu(olen);
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if (rc)
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return;
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opal_poll_events(NULL);
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} while (len < 1);
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olen = cpu_to_be64(1);
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opal_console_write(opal_con_id, &olen, &c);
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}
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static void opal_con_close(void)
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{
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opal_console_flush(opal_con_id);
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}
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static void opal_init(void)
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{
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void *opal_node;
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opal_node = finddevice("/ibm,opal");
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if (!opal_node)
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return;
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if (getprop(opal_node, "opal-base-address", &opal.base, sizeof(u64)) < 0)
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return;
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opal.base = be64_to_cpu(opal.base);
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if (getprop(opal_node, "opal-entry-address", &opal.entry, sizeof(u64)) < 0)
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return;
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opal.entry = be64_to_cpu(opal.entry);
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}
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int opal_console_init(void *devp, struct serial_console_data *scdp)
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{
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opal_init();
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if (devp) {
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int n = getprop(devp, "reg", &opal_con_id, sizeof(u32));
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if (n != sizeof(u32))
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return -1;
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opal_con_id = be32_to_cpu(opal_con_id);
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} else
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opal_con_id = 0;
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scdp->open = opal_con_open;
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scdp->putc = opal_con_putc;
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scdp->close = opal_con_close;
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return 0;
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}
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