1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Parse the EFI PCDP table to locate the console device. 4 * 5 * (c) Copyright 2002, 2003, 2004 Hewlett-Packard Development Company, L.P. 6 * Khalid Aziz <khalid.aziz@hp.com> 7 * Alex Williamson <alex.williamson@hp.com> 8 * Bjorn Helgaas <bjorn.helgaas@hp.com> 9 */ 10 11 #include <linux/acpi.h> 12 #include <linux/console.h> 13 #include <linux/efi.h> 14 #include <linux/serial.h> 15 #include <linux/serial_core.h> 16 #include <asm/vga.h> 17 #include "pcdp.h" 18 19 static int __init 20 setup_serial_console(struct pcdp_uart *uart) 21 { 22 #ifdef CONFIG_SERIAL_8250_CONSOLE 23 int mmio; 24 static char options[64], *p = options; 25 char parity; 26 27 mmio = (uart->addr.space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY); 28 p += sprintf(p, "uart8250,%s,0x%llx", 29 mmio ? "mmio" : "io", uart->addr.address); 30 if (uart->baud) { 31 p += sprintf(p, ",%llu", uart->baud); 32 if (uart->bits) { 33 switch (uart->parity) { 34 case 0x2: parity = 'e'; break; 35 case 0x3: parity = 'o'; break; 36 default: parity = 'n'; 37 } 38 p += sprintf(p, "%c%d", parity, uart->bits); 39 } 40 } 41 42 add_preferred_console("uart", 8250, &options[9]); 43 return setup_earlycon(options); 44 #else 45 return -ENODEV; 46 #endif 47 } 48 49 static int __init 50 setup_vga_console(struct pcdp_device *dev) 51 { 52 #if defined(CONFIG_VT) && defined(CONFIG_VGA_CONSOLE) 53 u8 *if_ptr; 54 55 if_ptr = ((u8 *)dev + sizeof(struct pcdp_device)); 56 if (if_ptr[0] == PCDP_IF_PCI) { 57 struct pcdp_if_pci if_pci; 58 59 /* struct copy since ifptr might not be correctly aligned */ 60 61 memcpy(&if_pci, if_ptr, sizeof(if_pci)); 62 63 if (if_pci.trans & PCDP_PCI_TRANS_IOPORT) 64 vga_console_iobase = if_pci.ioport_tra; 65 66 if (if_pci.trans & PCDP_PCI_TRANS_MMIO) 67 vga_console_membase = if_pci.mmio_tra; 68 } 69 70 if (efi_mem_type(vga_console_membase + 0xA0000) == EFI_CONVENTIONAL_MEMORY) { 71 printk(KERN_ERR "PCDP: VGA selected, but frame buffer is not MMIO!\n"); 72 return -ENODEV; 73 } 74 75 conswitchp = &vga_con; 76 printk(KERN_INFO "PCDP: VGA console\n"); 77 return 0; 78 #else 79 return -ENODEV; 80 #endif 81 } 82 83 int __init 84 efi_setup_pcdp_console(char *cmdline) 85 { 86 struct pcdp *pcdp; 87 struct pcdp_uart *uart; 88 struct pcdp_device *dev, *end; 89 int i, serial = 0; 90 int rc = -ENODEV; 91 92 if (efi.hcdp == EFI_INVALID_TABLE_ADDR) 93 return -ENODEV; 94 95 pcdp = early_memremap(efi.hcdp, 4096); 96 printk(KERN_INFO "PCDP: v%d at 0x%lx\n", pcdp->rev, efi.hcdp); 97 98 if (strstr(cmdline, "console=hcdp")) { 99 if (pcdp->rev < 3) 100 serial = 1; 101 } else if (strstr(cmdline, "console=")) { 102 printk(KERN_INFO "Explicit \"console=\"; ignoring PCDP\n"); 103 goto out; 104 } 105 106 if (pcdp->rev < 3 && efi_uart_console_only()) 107 serial = 1; 108 109 for (i = 0, uart = pcdp->uart; i < pcdp->num_uarts; i++, uart++) { 110 if (uart->flags & PCDP_UART_PRIMARY_CONSOLE || serial) { 111 if (uart->type == PCDP_CONSOLE_UART) { 112 rc = setup_serial_console(uart); 113 goto out; 114 } 115 } 116 } 117 118 end = (struct pcdp_device *) ((u8 *) pcdp + pcdp->length); 119 for (dev = (struct pcdp_device *) (pcdp->uart + pcdp->num_uarts); 120 dev < end; 121 dev = (struct pcdp_device *) ((u8 *) dev + dev->length)) { 122 if (dev->flags & PCDP_PRIMARY_CONSOLE) { 123 if (dev->type == PCDP_CONSOLE_VGA) { 124 rc = setup_vga_console(dev); 125 goto out; 126 } 127 } 128 } 129 130 out: 131 early_memunmap(pcdp, 4096); 132 return rc; 133 } 134