Skip to content

Commit

Permalink
---
Browse files Browse the repository at this point in the history
yaml
---
r: 212076
b: refs/heads/master
c: c20b5c3
h: refs/heads/master
v: v3
  • Loading branch information
Feng Tang authored and Ingo Molnar committed Oct 8, 2010
1 parent 87625f5 commit 07c830b
Show file tree
Hide file tree
Showing 6 changed files with 250 additions and 1 deletion.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: 5a47c7dae861c3ca3edf178546641909851bf715
refs/heads/master: c20b5c3318fe45e4f33f01a91ccead645dfdf619
4 changes: 4 additions & 0 deletions trunk/arch/x86/Kconfig.debug
Original file line number Diff line number Diff line change
Expand Up @@ -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
Expand Down
5 changes: 5 additions & 0 deletions trunk/arch/x86/include/asm/mrst.h
Original file line number Diff line number Diff line change
Expand Up @@ -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);

Expand Down Expand Up @@ -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 */
1 change: 1 addition & 0 deletions trunk/arch/x86/kernel/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -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
Expand Down
7 changes: 7 additions & 0 deletions trunk/arch/x86/kernel/early_printk.c
Original file line number Diff line number Diff line change
Expand Up @@ -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>

Expand Down Expand Up @@ -238,6 +239,12 @@ static int __init setup_early_printk(char *buf)
#ifdef CONFIG_HVC_XEN
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++;
}
Expand Down
232 changes: 232 additions & 0 deletions trunk/arch/x86/kernel/early_printk_mrst.c
Original file line number Diff line number Diff line change
@@ -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,
};

0 comments on commit 07c830b

Please sign in to comment.