diff options
Diffstat (limited to 'arch/x86/kernel/early_printk.c')
| -rw-r--r-- | arch/x86/kernel/early_printk.c | 265 |
1 files changed, 236 insertions, 29 deletions
diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c index d15f575a861b..cba75306e5b6 100644 --- a/arch/x86/kernel/early_printk.c +++ b/arch/x86/kernel/early_printk.c @@ -1,5 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0 #include <linux/console.h> #include <linux/kernel.h> +#include <linux/kexec.h> #include <linux/init.h> #include <linux/string.h> #include <linux/screen_info.h> @@ -7,6 +9,7 @@ #include <linux/pci_regs.h> #include <linux/pci_ids.h> #include <linux/errno.h> +#include <linux/pgtable.h> #include <asm/io.h> #include <asm/processor.h> #include <asm/fcntl.h> @@ -14,9 +17,10 @@ #include <xen/hvc-console.h> #include <asm/pci-direct.h> #include <asm/fixmap.h> -#include <asm/mrst.h> -#include <asm/pgtable.h> #include <linux/usb/ehci_def.h> +#include <linux/usb/xhci-dbgp.h> +#include <asm/pci_x86.h> +#include <linux/static_call.h> /* Simple VGA output */ #define VGABASE (__ISA_IO_base + 0xb8000) @@ -74,7 +78,7 @@ static struct console early_vga_console = { /* Serial functions loosely based on a similar package from Klaus P. Gerlicher */ -static int early_serial_base = 0x3f8; /* ttyS0 */ +static unsigned long early_serial_base = 0x3f8; /* ttyS0 */ #define XMTRDY 0x20 @@ -92,13 +96,28 @@ static int early_serial_base = 0x3f8; /* ttyS0 */ #define DLL 0 /* Divisor Latch Low */ #define DLH 1 /* Divisor latch High */ +static __noendbr unsigned int io_serial_in(unsigned long addr, int offset) +{ + return inb(addr + offset); +} +ANNOTATE_NOENDBR_SYM(io_serial_in); + +static __noendbr void io_serial_out(unsigned long addr, int offset, int value) +{ + outb(value, addr + offset); +} +ANNOTATE_NOENDBR_SYM(io_serial_out); + +DEFINE_STATIC_CALL(serial_in, io_serial_in); +DEFINE_STATIC_CALL(serial_out, io_serial_out); + static int early_serial_putc(unsigned char ch) { unsigned timeout = 0xffff; - while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout) + while ((static_call(serial_in)(early_serial_base, LSR) & XMTRDY) == 0 && --timeout) cpu_relax(); - outb(ch, early_serial_base + TXR); + static_call(serial_out)(early_serial_base, TXR, ch); return timeout ? 0 : -1; } @@ -112,13 +131,33 @@ static void early_serial_write(struct console *con, const char *s, unsigned n) } } +static __init void early_serial_hw_init(unsigned divisor) +{ + unsigned char c; + + static_call(serial_out)(early_serial_base, LCR, 0x3); /* 8n1 */ + static_call(serial_out)(early_serial_base, IER, 0); /* no interrupt */ + static_call(serial_out)(early_serial_base, FCR, 0); /* no fifo */ + static_call(serial_out)(early_serial_base, MCR, 0x3); /* DTR + RTS */ + + c = static_call(serial_in)(early_serial_base, LCR); + static_call(serial_out)(early_serial_base, LCR, c | DLAB); + static_call(serial_out)(early_serial_base, DLL, divisor & 0xff); + static_call(serial_out)(early_serial_base, DLH, (divisor >> 8) & 0xff); + static_call(serial_out)(early_serial_base, LCR, c & ~DLAB); + +#if defined(CONFIG_KEXEC_CORE) && defined(CONFIG_X86_64) + if (static_call_query(serial_in) == io_serial_in) + kexec_debug_8250_port = early_serial_base; +#endif +} + #define DEFAULT_BAUD 9600 static __init void early_serial_init(char *s) { - unsigned char c; unsigned divisor; - unsigned baud = DEFAULT_BAUD; + unsigned long baud = DEFAULT_BAUD; char *e; if (*s == ',') @@ -143,24 +182,186 @@ static __init void early_serial_init(char *s) s++; } - outb(0x3, early_serial_base + LCR); /* 8n1 */ - outb(0, early_serial_base + IER); /* no interrupt */ - outb(0, early_serial_base + FCR); /* no fifo */ - outb(0x3, early_serial_base + MCR); /* DTR + RTS */ - if (*s) { - baud = simple_strtoul(s, &e, 0); + baud = simple_strtoull(s, &e, 0); + if (baud == 0 || s == e) baud = DEFAULT_BAUD; } + /* Convert from baud to divisor value */ + divisor = 115200 / baud; + + /* Set up the HW */ + early_serial_hw_init(divisor); +} + +static __noendbr void mem32_serial_out(unsigned long addr, int offset, int value) +{ + u32 __iomem *vaddr = (u32 __iomem *)addr; + /* shift implied by pointer type */ + writel(value, vaddr + offset); +} +ANNOTATE_NOENDBR_SYM(mem32_serial_out); + +static __noendbr unsigned int mem32_serial_in(unsigned long addr, int offset) +{ + u32 __iomem *vaddr = (u32 __iomem *)addr; + /* shift implied by pointer type */ + return readl(vaddr + offset); +} +ANNOTATE_NOENDBR_SYM(mem32_serial_in); + +/* + * early_mmio_serial_init() - Initialize MMIO-based early serial console. + * @s: MMIO-based serial specification. + */ +static __init void early_mmio_serial_init(char *s) +{ + unsigned long baudrate; + unsigned long membase; + char *e; + + if (*s == ',') + s++; + + if (!strncmp(s, "0x", 2)) { + /* NB: only 32-bit addresses are supported. */ + membase = simple_strtoul(s, &e, 16); + early_serial_base = (unsigned long)early_ioremap(membase, PAGE_SIZE); + + static_call_update(serial_in, mem32_serial_in); + static_call_update(serial_out, mem32_serial_out); + + s += strcspn(s, ","); + if (*s == ',') + s++; + } + + if (!strncmp(s, "nocfg", 5)) { + baudrate = 0; + } else { + baudrate = simple_strtoul(s, &e, 0); + if (baudrate == 0 || s == e) + baudrate = DEFAULT_BAUD; + } + + if (baudrate) + early_serial_hw_init(115200 / baudrate); +} + +#ifdef CONFIG_PCI +/* + * early_pci_serial_init() + * + * This function is invoked when the early_printk param starts with "pciserial" + * The rest of the param should be "[force],B:D.F,baud", where B, D & F describe + * the location of a PCI device that must be a UART device. "force" is optional + * and overrides the use of an UART device with a wrong PCI class code. + */ +static __init void early_pci_serial_init(char *s) +{ + unsigned divisor; + unsigned long baud = DEFAULT_BAUD; + u8 bus, slot, func; + u32 classcode, bar0; + u16 cmdreg; + char *e; + int force = 0; + + if (*s == ',') + ++s; + + if (*s == 0) + return; + + /* Force the use of an UART device with wrong class code */ + if (!strncmp(s, "force,", 6)) { + force = 1; + s += 6; + } + + /* + * Part the param to get the BDF values + */ + bus = (u8)simple_strtoul(s, &e, 16); + s = e; + if (*s != ':') + return; + ++s; + slot = (u8)simple_strtoul(s, &e, 16); + s = e; + if (*s != '.') + return; + ++s; + func = (u8)simple_strtoul(s, &e, 16); + s = e; + + /* A baud might be following */ + if (*s == ',') + s++; + + /* + * Find the device from the BDF + */ + cmdreg = read_pci_config(bus, slot, func, PCI_COMMAND); + classcode = read_pci_config(bus, slot, func, PCI_CLASS_REVISION); + bar0 = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0); + + /* + * Verify it is a 16550-UART type device + */ + if (((classcode >> 16 != PCI_CLASS_COMMUNICATION_MODEM) && + (classcode >> 16 != PCI_CLASS_COMMUNICATION_SERIAL)) || + (((classcode >> 8) & 0xff) != PCI_SERIAL_16550_COMPATIBLE)) { + if (!force) + return; + } + + /* + * Determine if it is IO or memory mapped + */ + if ((bar0 & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) { + /* it is IO mapped */ + early_serial_base = bar0 & PCI_BASE_ADDRESS_IO_MASK; + write_pci_config(bus, slot, func, PCI_COMMAND, + cmdreg|PCI_COMMAND_IO); + } else { + /* It is memory mapped - assume 32-bit alignment */ + static_call_update(serial_in, mem32_serial_in); + static_call_update(serial_out, mem32_serial_out); + /* WARNING! assuming the address is always in the first 4G */ + early_serial_base = + (unsigned long)early_ioremap(bar0 & PCI_BASE_ADDRESS_MEM_MASK, 0x10); +#if defined(CONFIG_KEXEC_CORE) && defined(CONFIG_X86_64) + kexec_debug_8250_mmio32 = bar0 & PCI_BASE_ADDRESS_MEM_MASK; +#endif + write_pci_config(bus, slot, func, PCI_COMMAND, + cmdreg|PCI_COMMAND_MEMORY); + } + + /* + * Initialize the hardware + */ + if (*s) { + if (strcmp(s, "nocfg") == 0) + /* Sometimes, we want to leave the UART alone + * and assume the BIOS has set it up correctly. + * "nocfg" tells us this is the case, and we + * should do no more setup. + */ + return; + if (kstrtoul(s, 0, &baud) < 0 || baud == 0) + baud = DEFAULT_BAUD; + } + + /* Convert from baud to divisor value */ divisor = 115200 / baud; - c = inb(early_serial_base + LCR); - outb(c | DLAB, early_serial_base + LCR); - outb(divisor & 0xff, early_serial_base + DLL); - outb((divisor >> 8) & 0xff, early_serial_base + DLH); - outb(c & ~DLAB, early_serial_base + LCR); + + /* Set up the HW */ + early_serial_hw_init(divisor); } +#endif static struct console early_serial_console = { .name = "earlyser", @@ -169,7 +370,7 @@ static struct console early_serial_console = { .index = -1, }; -static inline void early_console_register(struct console *con, int keep_early) +static void early_console_register(struct console *con, int keep_early) { if (con->index != -1) { printk(KERN_CRIT "ERROR: earlyprintk= %s already used\n", @@ -197,6 +398,11 @@ static int __init setup_early_printk(char *buf) keep = (strstr(buf, "keep") != NULL); while (*buf != '\0') { + if (!strncmp(buf, "mmio32", 6)) { + buf += 6; + early_mmio_serial_init(buf); + early_console_register(&early_serial_console, keep); + } if (!strncmp(buf, "serial", 6)) { buf += 6; early_serial_init(buf); @@ -208,6 +414,13 @@ static int __init setup_early_printk(char *buf) early_serial_init(buf + 4); early_console_register(&early_serial_console, keep); } +#ifdef CONFIG_PCI + if (!strncmp(buf, "pciserial", 9)) { + buf += 9; /* Keep from match the above "pciserial" */ + early_pci_serial_init(buf); + early_console_register(&early_serial_console, keep); + } +#endif if (!strncmp(buf, "vga", 3) && boot_params.screen_info.orig_video_isVGA == 1) { max_xpos = boot_params.screen_info.orig_video_cols; @@ -223,17 +436,11 @@ static int __init setup_early_printk(char *buf) if (!strncmp(buf, "xen", 3)) early_console_register(&xenboot_console, keep); #endif -#ifdef CONFIG_EARLY_PRINTK_INTEL_MID - if (!strncmp(buf, "mrst", 4)) { - mrst_early_console_init(); - early_console_register(&early_mrst_console, keep); - } - - if (!strncmp(buf, "hsu", 3)) { - hsu_early_console_init(buf + 3); - early_console_register(&early_hsu_console, keep); - } +#ifdef CONFIG_EARLY_PRINTK_USB_XDBC + if (!strncmp(buf, "xdbc", 4)) + early_xdbc_parse_parameter(buf + 4, keep); #endif + buf++; } return 0; |