diff options
| -rw-r--r-- | arch/arm/mach-mxs/Kconfig | 4 | ||||
| -rw-r--r-- | arch/arm/mach-mxs/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm/mach-mxs/include/mach/common.h | 1 | ||||
| -rw-r--r-- | arch/arm/mach-mxs/ocotp.c | 90 |
4 files changed, 97 insertions, 0 deletions
diff --git a/arch/arm/mach-mxs/Kconfig b/arch/arm/mach-mxs/Kconfig index 8bfc8df54617..cd2fbdfc37e8 100644 --- a/arch/arm/mach-mxs/Kconfig +++ b/arch/arm/mach-mxs/Kconfig @@ -2,6 +2,9 @@ if ARCH_MXS source "arch/arm/mach-mxs/devices/Kconfig" +config MXS_OCOTP + bool + config SOC_IMX23 bool select CPU_ARM926T @@ -26,6 +29,7 @@ config MACH_MX28EVK select SOC_IMX28 select MXS_HAVE_AMBA_DUART select MXS_HAVE_PLATFORM_FEC + select MXS_OCOTP default y help Include support for MX28EVK platform. This includes specific diff --git a/arch/arm/mach-mxs/Makefile b/arch/arm/mach-mxs/Makefile index 39d3f9c2a841..df501a8340f2 100644 --- a/arch/arm/mach-mxs/Makefile +++ b/arch/arm/mach-mxs/Makefile @@ -1,6 +1,8 @@ # Common support obj-y := clock.o devices.o gpio.o icoll.o iomux.o system.o timer.o +obj-$(CONFIG_MXS_OCOTP) += ocotp.o + obj-$(CONFIG_SOC_IMX23) += clock-mx23.o mm-mx23.o obj-$(CONFIG_SOC_IMX28) += clock-mx28.o mm-mx28.o diff --git a/arch/arm/mach-mxs/include/mach/common.h b/arch/arm/mach-mxs/include/mach/common.h index 59133eb3cc96..635bb5d9a20a 100644 --- a/arch/arm/mach-mxs/include/mach/common.h +++ b/arch/arm/mach-mxs/include/mach/common.h @@ -13,6 +13,7 @@ struct clk; +extern const u32 *mxs_get_ocotp(void); extern int mxs_reset_block(void __iomem *); extern void mxs_timer_init(struct clk *, int); diff --git a/arch/arm/mach-mxs/ocotp.c b/arch/arm/mach-mxs/ocotp.c new file mode 100644 index 000000000000..65157a35dbba --- /dev/null +++ b/arch/arm/mach-mxs/ocotp.c @@ -0,0 +1,90 @@ +/* + * Copyright 2010 Freescale Semiconductor, Inc. All Rights Reserved. + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/mutex.h> + +#include <mach/mxs.h> + +#define OCOTP_WORD_OFFSET 0x20 +#define OCOTP_WORD_COUNT 0x20 + +#define BM_OCOTP_CTRL_BUSY (1 << 8) +#define BM_OCOTP_CTRL_ERROR (1 << 9) +#define BM_OCOTP_CTRL_RD_BANK_OPEN (1 << 12) + +static DEFINE_MUTEX(ocotp_mutex); +static u32 ocotp_words[OCOTP_WORD_COUNT]; + +const u32 *mxs_get_ocotp(void) +{ + void __iomem *ocotp_base = MXS_IO_ADDRESS(MXS_OCOTP_BASE_ADDR); + int timeout = 0x400; + size_t i; + static int once = 0; + + if (once) + return ocotp_words; + + mutex_lock(&ocotp_mutex); + + /* + * clk_enable(hbus_clk) for ocotp can be skipped + * as it must be on when system is running. + */ + + /* try to clear ERROR bit */ + __mxs_clrl(BM_OCOTP_CTRL_ERROR, ocotp_base); + + /* check both BUSY and ERROR cleared */ + while ((__raw_readl(ocotp_base) & + (BM_OCOTP_CTRL_BUSY | BM_OCOTP_CTRL_ERROR)) && --timeout) + cpu_relax(); + + if (unlikely(!timeout)) + goto error_unlock; + + /* open OCOTP banks for read */ + __mxs_setl(BM_OCOTP_CTRL_RD_BANK_OPEN, ocotp_base); + + /* approximately wait 32 hclk cycles */ + udelay(1); + + /* poll BUSY bit becoming cleared */ + timeout = 0x400; + while ((__raw_readl(ocotp_base) & BM_OCOTP_CTRL_BUSY) && --timeout) + cpu_relax(); + + if (unlikely(!timeout)) + goto error_unlock; + + for (i = 0; i < OCOTP_WORD_COUNT; i++) + ocotp_words[i] = __raw_readl(ocotp_base + OCOTP_WORD_OFFSET + + i * 0x10); + + /* close banks for power saving */ + __mxs_clrl(BM_OCOTP_CTRL_RD_BANK_OPEN, ocotp_base); + + once = 1; + + mutex_unlock(&ocotp_mutex); + + return ocotp_words; + +error_unlock: + mutex_unlock(&ocotp_mutex); + pr_err("%s: timeout in reading OCOTP\n", __func__); + return NULL; +} |