As preparatory to enable earlyprintk on non-standard ports on x86, introduce serial_in() and serial_out() helpers to perform serial I/O.
No functional change intended. Signed-off-by: Andy Shevchenko <[email protected]> --- arch/x86/boot/boot.h | 2 + .../boot/compressed/early_serial_console.c | 3 + arch/x86/boot/compressed/misc.c | 4 +- arch/x86/boot/compressed/misc.h | 4 ++ arch/x86/boot/early_serial_console.c | 63 +++++++++++++------ arch/x86/boot/tty.c | 7 ++- 6 files changed, 61 insertions(+), 22 deletions(-) diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h index f41291903da7..86641b2e83f8 100644 --- a/arch/x86/boot/boot.h +++ b/arch/x86/boot/boot.h @@ -299,6 +299,8 @@ int check_knl_erratum(void); int validate_cpu(void); /* early_serial_console.c */ +extern unsigned int (*serial_in)(unsigned long addr, int offset); +extern void (*serial_out)(unsigned long addr, int offset, int value); extern unsigned long early_serial_base; void console_init(void); diff --git a/arch/x86/boot/compressed/early_serial_console.c b/arch/x86/boot/compressed/early_serial_console.c index 5e3a66478754..4b6269624b59 100644 --- a/arch/x86/boot/compressed/early_serial_console.c +++ b/arch/x86/boot/compressed/early_serial_console.c @@ -1,5 +1,8 @@ #include "misc.h" +unsigned int (*serial_in)(unsigned long addr, int offset); +void (*serial_out)(unsigned long addr, int offset, int value); + unsigned long early_serial_base; #include "../early_serial_console.c" diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index c0d6c560df69..75b3c8bb92ac 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -98,10 +98,10 @@ static void serial_putchar(int ch) { unsigned timeout = 0xffff; - while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout) + while ((serial_in(early_serial_base, LSR) & XMTRDY) == 0 && --timeout) cpu_relax(); - outb(ch, early_serial_base + TXR); + serial_out(early_serial_base, TXR, ch); } void __putstr(const char *s) diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 6f2bdf813949..2fd3ec89a70d 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -110,9 +110,13 @@ static inline void finalize_identity_maps(void) #ifdef CONFIG_EARLY_PRINTK /* early_serial_console.c */ +extern unsigned int (*serial_in)(unsigned long addr, int offset); +extern void (*serial_out)(unsigned long addr, int offset, int value); extern unsigned long early_serial_base; void console_init(void); #else +static unsigned int (*serial_in)(unsigned long addr, int offset); +static void (*serial_out)(unsigned long addr, int offset, int value); static const unsigned long early_serial_base; static inline void console_init(void) { } diff --git a/arch/x86/boot/early_serial_console.c b/arch/x86/boot/early_serial_console.c index 2b663beda582..05d02cd4de99 100644 --- a/arch/x86/boot/early_serial_console.c +++ b/arch/x86/boot/early_serial_console.c @@ -23,22 +23,45 @@ #define DEFAULT_BAUD 9600 -static void early_serial_init(unsigned long port, int baud) +static unsigned int io_serial_in(unsigned long addr, int offset) +{ + return inb(addr + offset); +} + +static void io_serial_out(unsigned long addr, int offset, int value) +{ + outb(value, addr + offset); +} + +static void early_serial_configure(unsigned long port, int baud) { unsigned char c; unsigned divisor; - outb(0x3, port + LCR); /* 8n1 */ - outb(0, port + IER); /* no interrupt */ - outb(0, port + FCR); /* no fifo */ - outb(0x3, port + MCR); /* DTR + RTS */ + serial_out(port, LCR, 0x3); /* 8n1 */ + serial_out(port, IER, 0); /* no interrupt */ + serial_out(port, FCR, 0); /* no fifo */ + serial_out(port, MCR, 0x3); /* DTR + RTS */ divisor = 115200 / baud; - c = inb(port + LCR); - outb(c | DLAB, port + LCR); - outb(divisor & 0xff, port + DLL); - outb((divisor >> 8) & 0xff, port + DLH); - outb(c & ~DLAB, port + LCR); + c = serial_in(port, LCR); + serial_out(port, LCR, c | DLAB); + serial_out(port, DLL, divisor & 0xff); + serial_out(port, DLH, (divisor >> 8) & 0xff); + serial_out(port, LCR, c & ~DLAB); +} + +/* Assign serial I/O accessors */ +static void early_serial_use_io_accessors(void) +{ + /* These will always be IO based ports */ + serial_in = io_serial_in; + serial_out = io_serial_out; +} + +static void early_serial_init(unsigned long port, int baud) +{ + early_serial_configure(port, baud); early_serial_base = port; } @@ -73,6 +96,7 @@ static void parse_earlyprintk(void) port = DEFAULT_SERIAL_PORT; else pos = e - arg; + early_serial_use_io_accessors(); } else if (!strncmp(arg + pos, "ttyS", 4)) { static const int bases[] = { 0x3f8, 0x2f8 }; int idx = 0; @@ -84,6 +108,7 @@ static void parse_earlyprintk(void) idx = 1; port = bases[idx]; + early_serial_use_io_accessors(); } if (arg[pos] == ',') @@ -104,11 +129,11 @@ static unsigned int probe_baud(int port) unsigned char lcr, dll, dlh; unsigned int quot; - lcr = inb(port + LCR); - outb(lcr | DLAB, port + LCR); - dll = inb(port + DLL); - dlh = inb(port + DLH); - outb(lcr, port + LCR); + lcr = serial_in(port, LCR); + serial_out(port, LCR, lcr | DLAB); + dll = serial_in(port, DLL); + dlh = serial_in(port, DLH); + serial_out(port, LCR, lcr); quot = (dlh << 8) | dll; return BASE_BAUD / quot; @@ -129,11 +154,13 @@ static void parse_console_uart8250(void) options = optstr; - if (!strncmp(options, "uart8250,io,", 12)) + if (!strncmp(options, "uart8250,io,", 12)) { port = simple_strtoull(options + 12, &options, 0); - else if (!strncmp(options, "uart,io,", 8)) + early_serial_use_io_accessors(); + } else if (!strncmp(options, "uart,io,", 8)) { port = simple_strtoull(options + 8, &options, 0); - else + early_serial_use_io_accessors(); + } else return; if (options && (options[0] == ',')) diff --git a/arch/x86/boot/tty.c b/arch/x86/boot/tty.c index d1d34c6ca153..b6aa9db65cda 100644 --- a/arch/x86/boot/tty.c +++ b/arch/x86/boot/tty.c @@ -15,6 +15,9 @@ #include "boot.h" +unsigned int (*serial_in)(unsigned long addr, int offset); +void (*serial_out)(unsigned long addr, int offset, int value); + unsigned long early_serial_base; #define XMTRDY 0x20 @@ -31,10 +34,10 @@ static void __attribute__((section(".inittext"))) serial_putchar(int ch) { unsigned timeout = 0xffff; - while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout) + while ((serial_in(early_serial_base, LSR) & XMTRDY) == 0 && --timeout) cpu_relax(); - outb(ch, early_serial_base + TXR); + serial_out(early_serial_base, TXR, ch); } static void __attribute__((section(".inittext"))) bios_putchar(int ch) -- 2.20.1
