diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/Kconfig.debug | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/mrst.h | 5 | ||||
| -rw-r--r-- | arch/x86/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/early_printk.c | 7 | ||||
| -rw-r--r-- | arch/x86/kernel/early_printk_mrst.c | 232 |
5 files changed, 249 insertions, 0 deletions
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index 75085080b63e..e5bb96b10f1a 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -43,6 +43,10 @@ config EARLY_PRINTK with klogd/syslogd or the X server. You should normally N here, unless you want to debug such a crash. +config EARLY_PRINTK_MRST + bool "Early printk for MRST platform support" + depends on EARLY_PRINTK && X86_MRST + config EARLY_PRINTK_DBGP bool "Early printk via EHCI debug port" depends on EARLY_PRINTK && PCI diff --git a/arch/x86/include/asm/mrst.h b/arch/x86/include/asm/mrst.h index 33fc2966beb7..d0ea5bc505a3 100644 --- a/arch/x86/include/asm/mrst.h +++ b/arch/x86/include/asm/mrst.h @@ -10,6 +10,9 @@ */ #ifndef _ASM_X86_MRST_H #define _ASM_X86_MRST_H + +#include <linux/sfi.h> + extern int pci_mrst_init(void); int __init sfi_parse_mrtc(struct sfi_table_header *table); @@ -42,4 +45,6 @@ extern enum mrst_timer_options mrst_timer_options; #define SFI_MTMR_MAX_NUM 8 #define SFI_MRTC_MAX 8 +extern struct console early_mrst_console; +extern void mrst_early_console_init(void); #endif /* _ASM_X86_MRST_H */ diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index fedf32a8c3ec..3cd01d04613d 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -85,6 +85,7 @@ obj-$(CONFIG_DOUBLEFAULT) += doublefault_32.o obj-$(CONFIG_KGDB) += kgdb.o obj-$(CONFIG_VM86) += vm86_32.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o +obj-$(CONFIG_EARLY_PRINTK_MRST) += early_printk_mrst.o obj-$(CONFIG_HPET_TIMER) += hpet.o obj-$(CONFIG_APB_TIMER) += apb_timer.o diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c index fa99bae75ace..6082463768a2 100644 --- a/arch/x86/kernel/early_printk.c +++ b/arch/x86/kernel/early_printk.c @@ -14,6 +14,7 @@ #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> @@ -239,6 +240,12 @@ static int __init setup_early_printk(char *buf) if (!strncmp(buf, "xen", 3)) early_console_register(&xenboot_console, keep); #endif +#ifdef CONFIG_X86_MRST_EARLY_PRINTK + if (!strncmp(buf, "mrst", 4)) { + mrst_early_console_init(); + early_console_register(&early_mrst_console, keep); + } +#endif buf++; } return 0; diff --git a/arch/x86/kernel/early_printk_mrst.c b/arch/x86/kernel/early_printk_mrst.c new file mode 100644 index 000000000000..05d27e1e2b62 --- /dev/null +++ b/arch/x86/kernel/early_printk_mrst.c @@ -0,0 +1,232 @@ +/* + * early_printk_mrst.c - spi-uart early printk for Intel Moorestown platform + * + * Copyright (c) 2008-2010, Intel Corporation + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 + * of the License. + */ + +#include <linux/kmsg_dump.h> +#include <linux/console.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/io.h> + +#include <asm/fixmap.h> +#include <asm/pgtable.h> +#include <asm/mrst.h> + +#define MRST_SPI_TIMEOUT 0x200000 +#define MRST_REGBASE_SPI0 0xff128000 +#define MRST_REGBASE_SPI1 0xff128400 +#define MRST_CLK_SPI0_REG 0xff11d86c + +/* Bit fields in CTRLR0 */ +#define SPI_DFS_OFFSET 0 + +#define SPI_FRF_OFFSET 4 +#define SPI_FRF_SPI 0x0 +#define SPI_FRF_SSP 0x1 +#define SPI_FRF_MICROWIRE 0x2 +#define SPI_FRF_RESV 0x3 + +#define SPI_MODE_OFFSET 6 +#define SPI_SCPH_OFFSET 6 +#define SPI_SCOL_OFFSET 7 +#define SPI_TMOD_OFFSET 8 +#define SPI_TMOD_TR 0x0 /* xmit & recv */ +#define SPI_TMOD_TO 0x1 /* xmit only */ +#define SPI_TMOD_RO 0x2 /* recv only */ +#define SPI_TMOD_EPROMREAD 0x3 /* eeprom read mode */ + +#define SPI_SLVOE_OFFSET 10 +#define SPI_SRL_OFFSET 11 +#define SPI_CFS_OFFSET 12 + +/* Bit fields in SR, 7 bits */ +#define SR_MASK 0x7f /* cover 7 bits */ +#define SR_BUSY (1 << 0) +#define SR_TF_NOT_FULL (1 << 1) +#define SR_TF_EMPT (1 << 2) +#define SR_RF_NOT_EMPT (1 << 3) +#define SR_RF_FULL (1 << 4) +#define SR_TX_ERR (1 << 5) +#define SR_DCOL (1 << 6) + +struct dw_spi_reg { + u32 ctrl0; + u32 ctrl1; + u32 ssienr; + u32 mwcr; + u32 ser; + u32 baudr; + u32 txfltr; + u32 rxfltr; + u32 txflr; + u32 rxflr; + u32 sr; + u32 imr; + u32 isr; + u32 risr; + u32 txoicr; + u32 rxoicr; + u32 rxuicr; + u32 msticr; + u32 icr; + u32 dmacr; + u32 dmatdlr; + u32 dmardlr; + u32 idr; + u32 version; + + /* Currently operates as 32 bits, though only the low 16 bits matter */ + u32 dr; +} __packed; + +#define dw_readl(dw, name) __raw_readl(&(dw)->name) +#define dw_writel(dw, name, val) __raw_writel((val), &(dw)->name) + +/* Default use SPI0 register for mrst, we will detect Penwell and use SPI1 */ +static unsigned long mrst_spi_paddr = MRST_REGBASE_SPI0; + +static u32 *pclk_spi0; +/* Always contains an accessable address, start with 0 */ +static struct dw_spi_reg *pspi; + +static struct kmsg_dumper dw_dumper; +static int dumper_registered; + +static void dw_kmsg_dump(struct kmsg_dumper *dumper, + enum kmsg_dump_reason reason, + const char *s1, unsigned long l1, + const char *s2, unsigned long l2) +{ + int i; + + /* When run to this, we'd better re-init the HW */ + mrst_early_console_init(); + + for (i = 0; i < l1; i++) + early_mrst_console.write(&early_mrst_console, s1 + i, 1); + for (i = 0; i < l2; i++) + early_mrst_console.write(&early_mrst_console, s2 + i, 1); +} + +/* Set the ratio rate to 115200, 8n1, IRQ disabled */ +static void max3110_write_config(void) +{ + u16 config; + + config = 0xc001; + dw_writel(pspi, dr, config); +} + +/* Translate char to a eligible word and send to max3110 */ +static void max3110_write_data(char c) +{ + u16 data; + + data = 0x8000 | c; + dw_writel(pspi, dr, data); +} + +void mrst_early_console_init(void) +{ + u32 ctrlr0 = 0; + u32 spi0_cdiv; + u32 freq; /* Freqency info only need be searched once */ + + /* Base clk is 100 MHz, the actual clk = 100M / (clk_divider + 1) */ + pclk_spi0 = (void *)set_fixmap_offset_nocache(FIX_EARLYCON_MEM_BASE, + MRST_CLK_SPI0_REG); + spi0_cdiv = ((*pclk_spi0) & 0xe00) >> 9; + freq = 100000000 / (spi0_cdiv + 1); + + if (mrst_identify_cpu() == MRST_CPU_CHIP_PENWELL) + mrst_spi_paddr = MRST_REGBASE_SPI1; + + pspi = (void *)set_fixmap_offset_nocache(FIX_EARLYCON_MEM_BASE, + mrst_spi_paddr); + + /* Disable SPI controller */ + dw_writel(pspi, ssienr, 0); + + /* Set control param, 8 bits, transmit only mode */ + ctrlr0 = dw_readl(pspi, ctrl0); + + ctrlr0 &= 0xfcc0; + ctrlr0 |= 0xf | (SPI_FRF_SPI << SPI_FRF_OFFSET) + | (SPI_TMOD_TO << SPI_TMOD_OFFSET); + dw_writel(pspi, ctrl0, ctrlr0); + + /* + * Change the spi0 clk to comply with 115200 bps, use 100000 to + * calculate the clk dividor to make the clock a little slower + * than real baud rate. + */ + dw_writel(pspi, baudr, freq/100000); + + /* Disable all INT for early phase */ + dw_writel(pspi, imr, 0x0); + + /* Set the cs to spi-uart */ + dw_writel(pspi, ser, 0x2); + + /* Enable the HW, the last step for HW init */ + dw_writel(pspi, ssienr, 0x1); + + /* Set the default configuration */ + max3110_write_config(); + + /* Register the kmsg dumper */ + if (!dumper_registered) { + dw_dumper.dump = dw_kmsg_dump; + kmsg_dump_register(&dw_dumper); + dumper_registered = 1; + } +} + +/* Slave select should be called in the read/write function */ +static void early_mrst_spi_putc(char c) +{ + unsigned int timeout; + u32 sr; + + timeout = MRST_SPI_TIMEOUT; + /* Early putc needs to make sure the TX FIFO is not full */ + while (--timeout) { + sr = dw_readl(pspi, sr); + if (!(sr & SR_TF_NOT_FULL)) + cpu_relax(); + else + break; + } + + if (!timeout) + pr_warning("MRST earlycon: timed out\n"); + else + max3110_write_data(c); +} + +/* Early SPI only uses polling mode */ +static void early_mrst_spi_write(struct console *con, const char *str, unsigned n) +{ + int i; + + for (i = 0; i < n && *str; i++) { + if (*str == '\n') + early_mrst_spi_putc('\r'); + early_mrst_spi_putc(*str); + str++; + } +} + +struct console early_mrst_console = { + .name = "earlymrst", + .write = early_mrst_spi_write, + .flags = CON_PRINTBUFFER, + .index = -1, +}; |
