diff options
Diffstat (limited to 'drivers/firmware/pcdp.c')
| -rw-r--r-- | drivers/firmware/pcdp.c | 135 |
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; +} |