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Diffstat (limited to 'drivers/firmware/pcdp.c')
-rw-r--r--drivers/firmware/pcdp.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/drivers/firmware/pcdp.c b/drivers/firmware/pcdp.c
new file mode 100644
index 0000000000..715a45442d
--- /dev/null
+++ b/drivers/firmware/pcdp.c
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Parse the EFI PCDP table to locate the console device.
+ *
+ * (c) Copyright 2002, 2003, 2004 Hewlett-Packard Development Company, L.P.
+ * Khalid Aziz <khalid.aziz@hp.com>
+ * Alex Williamson <alex.williamson@hp.com>
+ * Bjorn Helgaas <bjorn.helgaas@hp.com>
+ */
+
+#include <linux/acpi.h>
+#include <linux/console.h>
+#include <linux/efi.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <asm/vga.h>
+#include "pcdp.h"
+
+static int __init
+setup_serial_console(struct pcdp_uart *uart)
+{
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+ int mmio;
+ static char options[64], *p = options;
+ char parity;
+
+ mmio = (uart->addr.space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY);
+ p += sprintf(p, "uart8250,%s,0x%llx",
+ mmio ? "mmio" : "io", uart->addr.address);
+ if (uart->baud) {
+ p += sprintf(p, ",%llu", uart->baud);
+ if (uart->bits) {
+ switch (uart->parity) {
+ case 0x2: parity = 'e'; break;
+ case 0x3: parity = 'o'; break;
+ default: parity = 'n';
+ }
+ p += sprintf(p, "%c%d", parity, uart->bits);
+ }
+ }
+
+ add_preferred_console("uart", 8250, &options[9]);
+ return setup_earlycon(options);
+#else
+ return -ENODEV;
+#endif
+}
+
+static int __init
+setup_vga_console(struct pcdp_device *dev)
+{
+#if defined(CONFIG_VT) && defined(CONFIG_VGA_CONSOLE)
+ u8 *if_ptr;
+
+ if_ptr = ((u8 *)dev + sizeof(struct pcdp_device));
+ if (if_ptr[0] == PCDP_IF_PCI) {
+ struct pcdp_if_pci if_pci;
+
+ /* struct copy since ifptr might not be correctly aligned */
+
+ memcpy(&if_pci, if_ptr, sizeof(if_pci));
+
+ if (if_pci.trans & PCDP_PCI_TRANS_IOPORT)
+ vga_console_iobase = if_pci.ioport_tra;
+
+ if (if_pci.trans & PCDP_PCI_TRANS_MMIO)
+ vga_console_membase = if_pci.mmio_tra;
+ }
+
+ if (efi_mem_type(vga_console_membase + 0xA0000) == EFI_CONVENTIONAL_MEMORY) {
+ printk(KERN_ERR "PCDP: VGA selected, but frame buffer is not MMIO!\n");
+ return -ENODEV;
+ }
+
+ conswitchp = &vga_con;
+ printk(KERN_INFO "PCDP: VGA console\n");
+ return 0;
+#else
+ return -ENODEV;
+#endif
+}
+
+extern unsigned long hcdp_phys;
+
+int __init
+efi_setup_pcdp_console(char *cmdline)
+{
+ struct pcdp *pcdp;
+ struct pcdp_uart *uart;
+ struct pcdp_device *dev, *end;
+ int i, serial = 0;
+ int rc = -ENODEV;
+
+ if (hcdp_phys == EFI_INVALID_TABLE_ADDR)
+ return -ENODEV;
+
+ pcdp = early_memremap(hcdp_phys, 4096);
+ printk(KERN_INFO "PCDP: v%d at 0x%lx\n", pcdp->rev, hcdp_phys);
+
+ if (strstr(cmdline, "console=hcdp")) {
+ if (pcdp->rev < 3)
+ serial = 1;
+ } else if (strstr(cmdline, "console=")) {
+ printk(KERN_INFO "Explicit \"console=\"; ignoring PCDP\n");
+ goto out;
+ }
+
+ if (pcdp->rev < 3 && efi_uart_console_only())
+ serial = 1;
+
+ for (i = 0, uart = pcdp->uart; i < pcdp->num_uarts; i++, uart++) {
+ if (uart->flags & PCDP_UART_PRIMARY_CONSOLE || serial) {
+ if (uart->type == PCDP_CONSOLE_UART) {
+ rc = setup_serial_console(uart);
+ goto out;
+ }
+ }
+ }
+
+ end = (struct pcdp_device *) ((u8 *) pcdp + pcdp->length);
+ for (dev = (struct pcdp_device *) (pcdp->uart + pcdp->num_uarts);
+ dev < end;
+ dev = (struct pcdp_device *) ((u8 *) dev + dev->length)) {
+ if (dev->flags & PCDP_PRIMARY_CONSOLE) {
+ if (dev->type == PCDP_CONSOLE_VGA) {
+ rc = setup_vga_console(dev);
+ goto out;
+ }
+ }
+ }
+
+out:
+ early_memunmap(pcdp, 4096);
+ return rc;
+}