Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756147AbaGIMiw (ORCPT ); Wed, 9 Jul 2014 08:38:52 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:60429 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755708AbaGIMiu (ORCPT ); Wed, 9 Jul 2014 08:38:50 -0400 From: Roger Quadros To: , CC: , , , , , , , , , Roger Quadros Subject: [RFC PATCH 07/10] OMAP: GPMC: Introduce APIs for Configuring ECC Engine Date: Wed, 9 Jul 2014 15:37:27 +0300 Message-ID: <1404909450-11970-8-git-send-email-rogerq@ti.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1404909450-11970-1-git-send-email-rogerq@ti.com> References: <1404909450-11970-1-git-send-email-rogerq@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Even though the ECC/BCH engine is meant for exclusive use by the OMAP NAND controller, the ECC/BCH registers belong to the GPMC controller's register space Add omap_gpmc_ecc_configure_enable() and omap_gpmc_ecc_disable() to manage the ECC engine. OMAP NAND driver must use these APIs instead of directly accessing the ECC Engine registers. Signed-off-by: Roger Quadros --- arch/arm/mach-omap2/gpmc.c | 109 ++++++++++++++++++++++++++++++++++++----- include/linux/omap-gpmc-nand.h | 25 ++++++++++ 2 files changed, 121 insertions(+), 13 deletions(-) diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c index 43e2a9d..8befd16 100644 --- a/arch/arm/mach-omap2/gpmc.c +++ b/arch/arm/mach-omap2/gpmc.c @@ -73,19 +73,6 @@ #define GPMC_ECC_BCH_RESULT_5 0x304 /* not available on OMAP2 */ #define GPMC_ECC_BCH_RESULT_6 0x308 /* not available on OMAP2 */ -/* GPMC ECC control settings */ -#define GPMC_ECC_CTRL_ECCCLEAR 0x100 -#define GPMC_ECC_CTRL_ECCDISABLE 0x000 -#define GPMC_ECC_CTRL_ECCREG1 0x001 -#define GPMC_ECC_CTRL_ECCREG2 0x002 -#define GPMC_ECC_CTRL_ECCREG3 0x003 -#define GPMC_ECC_CTRL_ECCREG4 0x004 -#define GPMC_ECC_CTRL_ECCREG5 0x005 -#define GPMC_ECC_CTRL_ECCREG6 0x006 -#define GPMC_ECC_CTRL_ECCREG7 0x007 -#define GPMC_ECC_CTRL_ECCREG8 0x008 -#define GPMC_ECC_CTRL_ECCREG9 0x009 - #define GPMC_CONFIG2_CSEXTRADELAY BIT(7) #define GPMC_CONFIG3_ADVEXTRADELAY BIT(7) #define GPMC_CONFIG4_OEEXTRADELAY BIT(7) @@ -129,6 +116,28 @@ #define GPMC_PREFETCH_STATUS_COUNT(val) (val & 0x00003fff) #define GPMC_PREFETCH_STATUS_FIFO_CNT(val) ((val >> 24) & 0x7F) +/* GPMC ECC config */ +#define GPMC_ECC_CONFIG_ECCENABLE BIT(0) +#define GPMC_ECC_CONFIG_ECCCS_MASK GENMASK(3, 1) +#define GPMC_ECC_CONFIG_ECCCS_SHIFT 1 +#define GPMC_ECC_CONFIG_ECCNSECTOR_MASK GENMASK(6, 4) +#define GPMC_ECC_CONFIG_ECCNSECTOR_SHIFT 4 +#define GPMC_ECC_CONFIG_ECC16B BIT(7) +#define GPMC_ECC_CONFIG_ECCWRAPMODE_MASK GENMASK(11, 8) +#define GPMC_ECC_CONFIG_ECCWRAPMODE_SHIFT 8 +#define GPMC_ECC_CONFIG_ECCBCHTSEL_MASK GENMASK(13, 12) +#define GPMC_ECC_CONFIG_ECCBCHTSEL_SHIFT 12 +#define GPMC_ECC_CONFIG_ECCALGBCH BIT(16) + +/* GPMC ECC control */ +#define GPMC_ECC_CONTROL_ECCCLEAR BIT(8) +#define GPMC_ECC_CONTROL_ECCPOINTER_MASK GENMASK(3, 0) +#define GPMC_ECC_CONTROL_ECCPOINTER_SHIFT 0 + +/* GPMC ECC size */ +#define GPMC_ECC_SIZE_ECCSIZE0_SHIFT 12 +#define GPMC_ECC_SIZE_ECCSIZE1_SHIFT 22 + /* XXX: Only NAND irq has been considered,currently these are the only ones used */ #define GPMC_NR_IRQ 2 @@ -2105,3 +2114,77 @@ u32 omap_gpmc_get_prefetch_fifo_count(void) count = GPMC_PREFETCH_STATUS_FIFO_CNT(count); return count; } + +/** + * omap_gpmc_ecc_disable - Disables the ECC engine + * but doesn't clear the ECC result registers. + */ +void omap_gpmc_ecc_disable(void) +{ + u32 val; + + /* Disable ECC engine if running */ + val = gpmc_read_reg(GPMC_ECC_CONFIG); + if (val & GPMC_ECC_CONFIG_ECCENABLE) { + val &= ~GPMC_ECC_CONFIG_ECCENABLE; + gpmc_write_reg(GPMC_ECC_CONFIG, val); + } +} + +/** + * omap_gpmc_ecc_configure_enable - Configures and enables the ECC-BCH engine + * + * @cs: chip select number + * @ecc16: true for 16-bit ECC column, false for 8-bit ECC columna + * @ecc_size0: This value is written to ECCSIZE0 of GPMC_ECC_SIZE_CONFIG reg. + * @ecc_size1: This value is written to ECCSIZE1 of GPMC_ECC_SIZE_CONFIG reg. + * @use_bch: true for BCH algorithm, false for 1-bit Hamming code algorithm + * @bch_type: enum omap_gpmc_bch_type, 4-bit, 8-bit or 16-bit BCH error + * correction cabability. Ignored if use_bch is false. + * @bch_sectors: No. of sectors to process with BCH. Ignored if use_bch false. + * @bch_wrap_mode: pre defined spare area defination for BCH calculation. + * Ignored if use_bch is false + */ +void omap_gpmc_ecc_configure_enable(int cs, bool ecc16, u8 ecc_size0, + u8 ecc_size1, bool use_bch, + enum omap_gpmc_bch_type bch_type, + u8 bch_sectors, u8 bch_wrap_mode) +{ + u32 val, valx; + + /* Disable ECC engine if running */ + omap_gpmc_ecc_disable(); + + /* Clear all ECC/BCH result registers */ + gpmc_write_reg(GPMC_ECC_CONTROL, GPMC_ECC_CONTROL_ECCCLEAR); + + /* ECC size */ + val = (ecc_size1 << GPMC_ECC_SIZE_ECCSIZE1_SHIFT) | + (ecc_size0 << GPMC_ECC_SIZE_ECCSIZE0_SHIFT); + gpmc_write_reg(GPMC_ECC_SIZE_CONFIG, val); + + /* ECC config */ + val = (cs << GPMC_ECC_CONFIG_ECCCS_SHIFT) & GPMC_ECC_CONFIG_ECCCS_MASK; + + if (ecc16) + val |= GPMC_ECC_CONFIG_ECC16B; + + if (use_bch) { + val |= GPMC_ECC_CONFIG_ECCALGBCH; + val |= (bch_type << GPMC_ECC_CONFIG_ECCBCHTSEL_SHIFT) & + GPMC_ECC_CONFIG_ECCBCHTSEL_MASK; + val |= (bch_sectors << GPMC_ECC_CONFIG_ECCNSECTOR_SHIFT) & + GPMC_ECC_CONFIG_ECCNSECTOR_MASK; + val |= (bch_wrap_mode << GPMC_ECC_CONFIG_ECCWRAPMODE_SHIFT) & + GPMC_ECC_CONFIG_ECCWRAPMODE_MASK; + } else { + /* Reset ECC result pointer to 1 */ + valx = (1 << GPMC_ECC_CONTROL_ECCPOINTER_SHIFT) & + GPMC_ECC_CONTROL_ECCPOINTER_MASK; + gpmc_write_reg(GPMC_ECC_CONTROL, valx); + } + + /* Enable ECC engine */ + val |= GPMC_ECC_CONFIG_ECCENABLE; + gpmc_write_reg(GPMC_ECC_CONFIG, val); +} diff --git a/include/linux/omap-gpmc-nand.h b/include/linux/omap-gpmc-nand.h index c445d89..f08cd05 100644 --- a/include/linux/omap-gpmc-nand.h +++ b/include/linux/omap-gpmc-nand.h @@ -23,6 +23,12 @@ enum omap_gpmc_reg { OMAP_GPMC_NAND_DATA, }; +enum omap_gpmc_bch_type { + OMAP_GPMC_BCH4, + OMAP_GPMC_BCH8, + OMAP_GPMC_BCH16, +}; + #ifdef CONFIG_ARCH_OMAP2PLUS u32 omap_gpmc_read_reg(int cs, enum omap_gpmc_reg reg); void omap_gpmc_write_reg(int cs, enum omap_gpmc_reg reg, u32 val); @@ -32,6 +38,11 @@ int omap_gpmc_prefetch_start(int cs, int fifo_th, bool dma, int omap_gpmc_prefetch_stop(int cs); u32 omap_gpmc_get_prefetch_count(void); u32 omap_gpmc_get_prefetch_fifo_count(void); +void omap_gpmc_ecc_disable(void); +void omap_gpmc_ecc_configure_enable(int cs, bool ecc16, u8 ecc_size0, + u8 ecc_size1, bool use_bch, + enum omap_gpmc_bch_type bch_type, + u8 bch_sectors, u8 bch_wrap_mode); #else static inline u32 omap_gpmc_read_reg(int cs, enum omap_gpmc_reg reg) { @@ -62,6 +73,20 @@ static inline u32 omap_gpmc_get_prefetch_fifo_count(void) { return 0; } + +static inline void omap_gpmc_ecc_disable(void) +{ +} + +static inline void omap_gpmc_ecc_configure_enable(int cs, bool ecc16, + u8 ecc_size0, u8 ecc_size1, + bool use_bch, + enum omap_gpmc_bch_type bch_type, + u8 bch_sectors, + u8 bch_wrap_mode) +{ +} + #endif /* Prefetch/Write-post Engine */ -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/