From: "Ghorai, Sukumar" <s-ghorai@ti.com>
To: Vimal Singh <vimal.newwork@gmail.com>
Cc: "linux-omap@vger.kernel.org" <linux-omap@vger.kernel.org>,
"Artem.Bityutskiy@nokia.com" <Artem.Bityutskiy@nokia.com>,
"tony@atomide.com" <tony@atomide.com>,
"sakoman@gmail.com" <sakoman@gmail.com>,
"linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>
Subject: RE: [PATCH v2 1/2] omap3 nand: cleanup for not to use GPMC virtual address
Date: Mon, 17 May 2010 09:52:40 +0530 [thread overview]
Message-ID: <2A3DCF3DA181AD40BDE86A3150B27B6B030D8FB75B@dbde02.ent.ti.com> (raw)
In-Reply-To: <AANLkTinGirx4-PPkpPhYEutbnN_uIPoYbA7BlUPCPnaK@mail.gmail.com>
Vimal,
> -----Original Message-----
> From: Vimal Singh [mailto:vimal.newwork@gmail.com]
> Sent: 2010-05-14 23:33
> To: Ghorai, Sukumar
> Cc: linux-omap@vger.kernel.org; Artem.Bityutskiy@nokia.com;
> tony@atomide.com; sakoman@gmail.com; linux-mtd@lists.infradead.org
> Subject: Re: [PATCH v2 1/2] omap3 nand: cleanup for not to use GPMC
> virtual address
>
> On Fri, May 14, 2010 at 8:53 PM, Sukumar Ghorai <s-ghorai@ti.com> wrote:
> [...]
>
> > diff --git a/arch/arm/mach-omap2/gpmc-onenand.c b/arch/arm/mach-
> omap2/gpmc-onenand.c
> > index 7bb6922..5d66817
> > --- a/arch/arm/mach-omap2/gpmc-onenand.c
> > +++ b/arch/arm/mach-omap2/gpmc-onenand.c
> > @@ -301,7 +301,7 @@ static int omap2_onenand_set_sync_mode(struct
> omap_onenand_platform_data *cfg,
> > (GPMC_CONFIG1_WAIT_READ_MON |
> > GPMC_CONFIG1_WAIT_PIN_SEL(0))) |
> > GPMC_CONFIG1_DEVICESIZE_16 |
> > - GPMC_CONFIG1_DEVICETYPE_NOR |
> > + GPMC_CONFIG1_DEVICETYPE(GPMC_DEVICETYPE_NOR) |
> > GPMC_CONFIG1_MUXADDDATA);
>
> Please do not dp OneNAND changes in NAND patch.
[Ghorai] I agree.
>
> > diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
> > index 5bc3ca0..a3fd1ed
> > --- a/arch/arm/mach-omap2/gpmc.c
> > +++ b/arch/arm/mach-omap2/gpmc.c
> > @@ -29,27 +29,27 @@
> > #include <plat/sdrc.h>
> >
> > /* GPMC register offsets */
> > -#define GPMC_REVISION 0x00
> > -#define GPMC_SYSCONFIG 0x10
> > -#define GPMC_SYSSTATUS 0x14
> > -#define GPMC_IRQSTATUS 0x18
> > -#define GPMC_IRQENABLE 0x1c
> > -#define GPMC_TIMEOUT_CONTROL 0x40
> > -#define GPMC_ERR_ADDRESS 0x44
> > -#define GPMC_ERR_TYPE 0x48
> > -#define GPMC_CONFIG 0x50
> > -#define GPMC_STATUS 0x54
> > -#define GPMC_PREFETCH_CONFIG1 0x1e0
> > -#define GPMC_PREFETCH_CONFIG2 0x1e4
> > -#define GPMC_PREFETCH_CONTROL 0x1ec
> > -#define GPMC_PREFETCH_STATUS 0x1f0
> > -#define GPMC_ECC_CONFIG 0x1f4
> > -#define GPMC_ECC_CONTROL 0x1f8
> > -#define GPMC_ECC_SIZE_CONFIG 0x1fc
> > -
> > -#define GPMC_CS0 0x60
> > -#define GPMC_CS_SIZE 0x30
> > -
> > +#define GPMC_REVISION 0x00
> > +#define GPMC_SYSCONFIG 0x10
> > +#define GPMC_SYSSTATUS 0x14
> > +#define GPMC_IRQSTATUS 0x18
> > +#define GPMC_IRQENABLE 0x1c
> > +#define GPMC_TIMEOUT_CONTROL 0x40
> > +#define GPMC_ERR_ADDRESS 0x44
> > +#define GPMC_ERR_TYPE 0x48
> > +#define GPMC_CONFIG 0x50
> > +#define GPMC_STATUS 0x54
> > +#define GPMC_PREFETCH_CONFIG1 0x1e0
> > +#define GPMC_PREFETCH_CONFIG2 0x1e4
> > +#define GPMC_PREFETCH_CONTROL 0x1ec
> > +#define GPMC_PREFETCH_STATUS 0x1f0
> > +#define GPMC_ECC_CONFIG 0x1f4
> > +#define GPMC_ECC_CONTROL 0x1f8
> > +#define GPMC_ECC_SIZE_CONFIG 0x1fc
> > +#define GPMC_ECC1_RESULT 0x200
> > +
> > +#define GPMC_CS0_BASE 0x60
> > +#define GPMC_CS_SIZE 0x30
> > #define GPMC_MEM_START 0x00000000
> > #define GPMC_MEM_END 0x3FFFFFFF
> > #define BOOT_ROM_SPACE 0x100000 /* 1MB */
> > @@ -108,11 +108,27 @@ static u32 gpmc_read_reg(int idx)
> > return __raw_readl(gpmc_base + idx);
> > }
> >
> > +static void gpmc_cs_write_byte(int cs, int idx, u8 val)
> > +{
> > + void __iomem *reg_addr;
> > +
> > + reg_addr = gpmc_base + GPMC_CS0_BASE + (cs * GPMC_CS_SIZE) +
> idx;
> > + __raw_writeb(val, reg_addr);
> > +}
> > +
> > +static u8 gpmc_cs_read_byte(int cs, int idx)
> > +{
> > + void __iomem *reg_addr;
> > +
> > + reg_addr = gpmc_base + GPMC_CS0_BASE + (cs * GPMC_CS_SIZE) +
> idx;
> > + return __raw_readb(reg_addr);
> > +}
> > +
>
> I do not think we need these functions.
[Ghorai] This is used in gpmc_hwcontrol() and to get the nand status from omap2.c.
>
> > void gpmc_cs_write_reg(int cs, int idx, u32 val)
> > {
> > void __iomem *reg_addr;
> >
> > - reg_addr = gpmc_base + GPMC_CS0 + (cs * GPMC_CS_SIZE) + idx;
> > + reg_addr = gpmc_base + GPMC_CS0_BASE + (cs * GPMC_CS_SIZE) +
> idx;
> > __raw_writel(val, reg_addr);
> > }
> >
> > @@ -120,7 +136,7 @@ u32 gpmc_cs_read_reg(int cs, int idx)
> > {
> > void __iomem *reg_addr;
> >
> > - reg_addr = gpmc_base + GPMC_CS0 + (cs * GPMC_CS_SIZE) + idx;
> > + reg_addr = gpmc_base + GPMC_CS0_BASE + (cs * GPMC_CS_SIZE) +
> idx;
> > return __raw_readl(reg_addr);
> > }
> >
> > @@ -419,6 +435,96 @@ void gpmc_cs_free(int cs)
> > EXPORT_SYMBOL(gpmc_cs_free);
> >
> > /**
> > + * gpmc_hwcontrol - hardware specific access (read/ write) to control
> > + * @write: need 1 for configure; 0 for reading the complete register
> > + * @cs: chip select number
> > + * @cmd: Command type
> > + * @wval: value/information to write
> > + * @rval: pointer to get the value back
> > + */
> > +int gpmc_hwcontrol(int write, int cs, int cmd, int wval, int *rval)
> > +{
> > + u32 reg = 0;
> > + u32 regval = 0;
> > +
> > + switch (cmd) {
> > +
> > + case GPMC_GET_SET_STATUS:
> > + reg = GPMC_STATUS;
> > + if (write)
> > + gpmc_write_reg(GPMC_STATUS, regval);
> > + break;
> > +
> > + case GPMC_GET_SET_IRQ_STATUS:
> > + reg = GPMC_IRQSTATUS;
> > + if (write)
> > + gpmc_write_reg(GPMC_IRQSTATUS, regval);
> > + break;
> > +
> > + case GPMC_GET_PREF_STATUS:
> > + reg = GPMC_PREFETCH_STATUS;
> > + break;
> > +
> > + case GPMC_CONFIG_WP:
> > + reg = GPMC_CONFIG;
> > + regval = gpmc_read_reg(GPMC_CONFIG);
> > + if (wval)
> > + regval &= ~GPMC_CONFIG_WRITEPROTECT; /* WP is ON
> */
> > + else
> > + regval |= GPMC_CONFIG_WRITEPROTECT; /* WP is
> OFF */
> > + gpmc_write_reg(reg, regval);
> > + break;
> > +
> > + case GPMC_CONFIG_RDY_BSY:
> > + #define WR_RD_PIN_MONITORING 0x00600000
> > + regval = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
> > + regval |= WR_RD_PIN_MONITORING;
> > + gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, regval);
> > + break;
> > +
> > + case GPMC_CONFIG_DEV_SIZE:
> > + regval = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
> > + regval |= GPMC_CONFIG1_DEVICESIZE(wval);
> > + gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, regval);
> > + break;
> > +
> > + case GPMC_CONFIG_DEV_TYPE:
> > + regval = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
> > + regval |= GPMC_CONFIG1_DEVICETYPE(wval);
> > + if (wval == GPMC_DEVICETYPE_NOR)
> > + regval |= GPMC_CONFIG1_MUXADDDATA;
> > + gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, regval);
> > + break;
> > +
> > + case GPMC_NAND_COMMAND:
> > + gpmc_cs_write_byte(cs, GPMC_CS_NAND_COMMAND, wval);
> > + break;
> > +
> > + case GPMC_NAND_ADDRESS:
> > + gpmc_cs_write_byte(cs, GPMC_CS_NAND_ADDRESS, wval);
> > + break;
> > +
> > + case GPMC_NAND_DATA:
> > + if (write)
> > + gpmc_cs_write_byte(cs, GPMC_CS_NAND_DATA, wval);
> > + else
> > + *rval = gpmc_cs_read_byte(cs,
> GPMC_CS_NAND_DATA);
> > + break;
> > +
> > + default:
> > + dump_stack();
> > + printk(KERN_ERR "not supported\n");
> > + return -1;
> > + }
> > +
> > + if (!write && reg)
> > + *rval = gpmc_read_reg(reg);
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(gpmc_hwcontrol);
> > +
> > +/**
> > * gpmc_prefetch_enable - configures and starts prefetch transfer
> > * @cs: nand cs (chip select) number
> > * @dma_mode: dma mode enable (1) or disable (0)
> > @@ -466,15 +572,6 @@ void gpmc_prefetch_reset(void)
> > }
> > EXPORT_SYMBOL(gpmc_prefetch_reset);
> >
> > -/**
> > - * gpmc_prefetch_status - reads prefetch status of engine
> > - */
> > -int gpmc_prefetch_status(void)
> > -{
> > - return gpmc_read_reg(GPMC_PREFETCH_STATUS);
> > -}
> > -EXPORT_SYMBOL(gpmc_prefetch_status);
> > -
> > static void __init gpmc_mem_init(void)
> > {
> > int cs;
> > @@ -615,3 +712,86 @@ void omap3_gpmc_restore_context(void)
> > }
> > }
> > #endif /* CONFIG_ARCH_OMAP3 */
> > +
> > +/**
> > + * gmpc_ecc_init - Initialize the HW ECC for NAND flash in GPMC
> controller
> > + * @cs: Chip select number
> > + * @ecc_size: bytes for which ECC will be generated
> > + */
> > +void gpmc_ecc_init(int cs, int ecc_size)
> > +{
> > + unsigned int val = 0x0;
> > +
> > + /* Read from ECC Control Register */
> > + val = gpmc_read_reg(GPMC_ECC_CONTROL);
> > +
> > + /* Clear all ECC | Enable Reg1 */
> > + val = ((0x00000001<<8) | 0x00000001);
> > + gpmc_write_reg(GPMC_ECC_CONTROL, val);
> > +
> > + /* Read from ECC Size Config Register */
> > + val = gpmc_read_reg(GPMC_ECC_SIZE_CONFIG);
> > + /* ECCSIZE1=512 | Select eccResultsize[0-3] */
> > + val = ((((ecc_size >> 1) - 1) << 22) | (0x0000000F));
> > + gpmc_write_reg(GPMC_ECC_SIZE_CONFIG, val);
> > +}
> > +
> > +/**
> > + * gpmc_calcuate_ecc - Generate non-inverted ECC bytes.
> > + * @cs: Chip select number
> > + * @dat: The pointer to data on which ecc is computed
> > + * @ecc_code: The ecc_code buffer
> > + *
> > + * Using noninverted ECC can be considered ugly since writing a blank
> > + * page ie. padding will clear the ECC bytes. This is no problem as
> long
> > + * nobody is trying to write data on the seemingly unused page. Reading
> > + * an erased page will produce an ECC mismatch between generated and
> read
> > + * ECC bytes that has to be dealt with separately.
> > + */
> > +int gpmc_calculate_ecc(int cs, const u_char *dat, u_char *ecc_code)
> > +{
> > + unsigned int val = 0x0;
> > +
> > + /* Start Reading from HW ECC1_Result = 0x200 */
> > + val = gpmc_read_reg(GPMC_ECC1_RESULT);
> > + *ecc_code++ = val; /* P128e, ..., P1e */
> > + *ecc_code++ = val >> 16; /* P128o, ..., P1o */
> > + /* P2048o, P1024o, P512o, P256o, P2048e, P1024e, P512e, P256e */
> > + *ecc_code++ = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0);
> > +
> > + return 0;
> > +}
> > +
> > +/**
> > + * gpmc_enable_hwecc - This function enables the hardware ecc
> functionality
> > + * @cs: Chip select number
> > + * @mode: Read/Write mode
> > + * @dev_width: device bus width
> > + */
> > +void gpmc_enable_hwecc(int cs, int mode, int dev_width)
> > +{
> > + unsigned int val = gpmc_read_reg(GPMC_ECC_CONFIG);
> > +
> > + switch (mode) {
> > + case GPMC_ECC_READ:
> > + gpmc_write_reg(GPMC_ECC_CONTROL, 0x101);
> > + /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
> > + val = (dev_width << 7) | (cs << 1) | (0x1);
> > + break;
> > + case GPMC_ECC_READSYN:
> > + gpmc_write_reg(GPMC_ECC_CONTROL, 0x100);
> > + /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
> > + val = (dev_width << 7) | (cs << 1) | (0x1);
> > + break;
> > + case GPMC_ECC_WRITE:
> > + gpmc_write_reg(GPMC_ECC_CONTROL, 0x101);
> > + /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
> > + val = (dev_width << 7) | (cs << 1) | (0x1);
> > + break;
> > + default:
> > + printk(KERN_INFO "Error: Unrecognized Mode[%d]!\n",
> mode);
> > + break;
> > + }
> > +
> > + gpmc_write_reg(GPMC_ECC_CONFIG, val);
> > +}
> > diff --git a/arch/arm/plat-omap/include/plat/gpmc.h b/arch/arm/plat-
> omap/include/plat/gpmc.h
> > index 145838a..56e1407
> > --- a/arch/arm/plat-omap/include/plat/gpmc.h
> > +++ b/arch/arm/plat-omap/include/plat/gpmc.h
> > @@ -25,10 +25,22 @@
> > #define GPMC_CS_NAND_ADDRESS 0x20
> > #define GPMC_CS_NAND_DATA 0x24
> >
> > -#define GPMC_CONFIG 0x50
> > -#define GPMC_STATUS 0x54
> > -#define GPMC_CS0_BASE 0x60
> > -#define GPMC_CS_SIZE 0x30
> > +/* Control Commands */
> > +#define GPMC_GET_SET_STATUS 0x00000001
> > +#define GPMC_CONFIG_WP 0x00000002
> > +#define GPMC_CONFIG_RDY_BSY 0x00000003
> > +#define GPMC_CONFIG_DEV_SIZE 0x00000004
> > +#define GPMC_CONFIG_DEV_TYPE 0x00000005
> > +#define GPMC_NAND_COMMAND 0x00000006
> > +#define GPMC_NAND_ADDRESS 0x00000007
> > +#define GPMC_NAND_DATA 0x00000008
> > +#define GPMC_GET_PREF_STATUS 0x00000009
> > +#define GPMC_GET_SET_IRQ_STATUS 0x0000000a
> > +
> > +/* ECC commands */
> > +#define GPMC_ECC_READ 0 /* Reset Hardware ECC for read */
> > +#define GPMC_ECC_WRITE 1 /* Reset Hardware ECC for write */
> > +#define GPMC_ECC_READSYN 2 /* Reset before syndrom is read back
> */
> >
> > #define GPMC_CONFIG1_WRAPBURST_SUPP (1 << 31)
> > #define GPMC_CONFIG1_READMULTIPLE_SUPP (1 << 30)
> > @@ -44,10 +56,7 @@
> > #define GPMC_CONFIG1_WAIT_MON_IIME(val) ((val & 3) << 18)
> > #define GPMC_CONFIG1_WAIT_PIN_SEL(val) ((val & 3) << 16)
> > #define GPMC_CONFIG1_DEVICESIZE(val) ((val & 3) << 12)
> > -#define GPMC_CONFIG1_DEVICESIZE_16 GPMC_CONFIG1_DEVICESIZE(1)
> > #define GPMC_CONFIG1_DEVICETYPE(val) ((val & 3) << 10)
> > -#define GPMC_CONFIG1_DEVICETYPE_NOR GPMC_CONFIG1_DEVICETYPE(0)
> > -#define GPMC_CONFIG1_DEVICETYPE_NAND GPMC_CONFIG1_DEVICETYPE(2)
> > #define GPMC_CONFIG1_MUXADDDATA (1 << 9)
> > #define GPMC_CONFIG1_TIME_PARA_GRAN (1 << 4)
> > #define GPMC_CONFIG1_FCLK_DIV(val) (val & 3)
> > @@ -56,6 +65,12 @@
> > #define GPMC_CONFIG1_FCLK_DIV4 (GPMC_CONFIG1_FCLK_DIV(3))
> > #define GPMC_CONFIG7_CSVALID (1 << 6)
> >
> > +#define GPMC_DEVICETYPE_NOR 0
> > +#define GPMC_DEVICETYPE_NAND 2
> > +#define GPMC_CONFIG_WRITEPROTECT 0x00000010
> > +#define GPMC_CONFIG1_DEVICESIZE_16 GPMC_CONFIG1_DEVICESIZE(1)
> > +
> > +
> > /*
> > * Note that all values in this struct are in nanoseconds, while
> > * the register values are in gpmc_fck cycles.
> > @@ -109,9 +124,14 @@ extern int gpmc_cs_reserved(int cs);
> > extern int gpmc_prefetch_enable(int cs, int dma_mode,
> > unsigned int u32_count, int
> is_write);
> > extern void gpmc_prefetch_reset(void);
> > -extern int gpmc_prefetch_status(void);
> > extern void omap3_gpmc_save_context(void);
> > extern void omap3_gpmc_restore_context(void);
> > extern void gpmc_init(void);
> > +extern int gpmc_hwcontrol(int write, int cs, int cmd, int wval, int
> *rval);
> > +
> > +void gpmc_ecc_init(int cs, int ecc_size);
> > +void gpmc_enable_hwecc(int cs, int mode, int dev_width);
> > +int gpmc_calculate_ecc(int cs, const u_char *dat, u_char *ecc_code);
> > +
> >
> > #endif
> > diff --git a/arch/arm/plat-omap/include/plat/nand.h b/arch/arm/plat-
> omap/include/plat/nand.h
> > index f8efd54..6562cd0
> > --- a/arch/arm/plat-omap/include/plat/nand.h
> > +++ b/arch/arm/plat-omap/include/plat/nand.h
> > @@ -21,13 +21,11 @@ struct omap_nand_platform_data {
> > int (*dev_ready)(struct
> omap_nand_platform_data *);
> > int dma_channel;
> > unsigned long phys_base;
> > - void __iomem *gpmc_cs_baseaddr;
> > - void __iomem *gpmc_baseaddr;
> > int devsize;
> > };
> >
> > -/* size (4 KiB) for IO mapping */
> > -#define NAND_IO_SIZE SZ_4K
> > +/* minimum size for IO mapping */
> > +#define NAND_IO_SIZE 4
> >
> > #if defined(CONFIG_MTD_NAND_OMAP2) ||
> defined(CONFIG_MTD_NAND_OMAP2_MODULE)
> > extern int gpmc_nand_init(struct omap_nand_platform_data *d);
> > diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
> > index 7545568..1858c42
> > --- a/drivers/mtd/nand/omap2.c
> > +++ b/drivers/mtd/nand/omap2.c
> > @@ -23,12 +23,6 @@
> > #include <plat/gpmc.h>
> > #include <plat/nand.h>
> >
> > -#define GPMC_IRQ_STATUS 0x18
> > -#define GPMC_ECC_CONFIG 0x1F4
> > -#define GPMC_ECC_CONTROL 0x1F8
> > -#define GPMC_ECC_SIZE_CONFIG 0x1FC
> > -#define GPMC_ECC1_RESULT 0x200
> > -
> > #define DRIVER_NAME "omap2-nand"
> >
> > #define NAND_WP_OFF 0
> > @@ -37,6 +31,7 @@
> > #define GPMC_BUF_FULL 0x00000001
> > #define GPMC_BUF_EMPTY 0x00000000
> >
> > +#ifdef CONFIG_MTD_NAND_OMAP_HWECC
> > #define NAND_Ecc_P1e (1 << 0)
> > #define NAND_Ecc_P2e (1 << 1)
> > #define NAND_Ecc_P4e (1 << 2)
> > @@ -103,6 +98,7 @@
> >
> > #define P4e_s(a) (TF(a & NAND_Ecc_P4e) << 0)
> > #define P4o_s(a) (TF(a & NAND_Ecc_P4o) << 1)
> > +#endif /* CONFIG_MTD_NAND_OMAP_HWECC */
>
> Why this ifdef macro?
>
> >
> > #ifdef CONFIG_MTD_PARTITIONS
> > static const char *part_probes[] = { "cmdlinepart", NULL };
> > @@ -139,34 +135,11 @@ struct omap_nand_info {
> >
> > int gpmc_cs;
> > unsigned long phys_base;
> > - void __iomem *gpmc_cs_baseaddr;
> > - void __iomem *gpmc_baseaddr;
> > - void __iomem *nand_pref_fifo_add;
> > struct completion comp;
> > int dma_ch;
> > };
> >
> > /**
> > - * omap_nand_wp - This function enable or disable the Write Protect
> feature
> > - * @mtd: MTD device structure
> > - * @mode: WP ON/OFF
> > - */
> > -static void omap_nand_wp(struct mtd_info *mtd, int mode)
> > -{
> > - struct omap_nand_info *info = container_of(mtd,
> > - struct omap_nand_info,
> mtd);
> > -
> > - unsigned long config = __raw_readl(info->gpmc_baseaddr +
> GPMC_CONFIG);
> > -
> > - if (mode)
> > - config &= ~(NAND_WP_BIT); /* WP is ON */
> > - else
> > - config |= (NAND_WP_BIT); /* WP is OFF */
> > -
> > - __raw_writel(config, (info->gpmc_baseaddr + GPMC_CONFIG));
> > -}
> > -
> > -/**
> > * omap_hwcontrol - hardware specific access to control-lines
> > * @mtd: MTD device structure
> > * @cmd: command to device
> > @@ -181,31 +154,20 @@ static void omap_hwcontrol(struct mtd_info *mtd,
> int cmd, unsigned int ctrl)
> > {
> > struct omap_nand_info *info = container_of(mtd,
> > struct omap_nand_info, mtd);
> > - switch (ctrl) {
> > - case NAND_CTRL_CHANGE | NAND_CTRL_CLE:
> > - info->nand.IO_ADDR_W = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_COMMAND;
> > - info->nand.IO_ADDR_R = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_DATA;
> > - break;
> > -
> > - case NAND_CTRL_CHANGE | NAND_CTRL_ALE:
> > - info->nand.IO_ADDR_W = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_ADDRESS;
> > - info->nand.IO_ADDR_R = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_DATA;
> > - break;
> > -
> > - case NAND_CTRL_CHANGE | NAND_NCE:
> > - info->nand.IO_ADDR_W = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_DATA;
> > - info->nand.IO_ADDR_R = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_DATA;
> > - break;
> > - }
> >
> > - if (cmd != NAND_CMD_NONE)
> > - __raw_writeb(cmd, info->nand.IO_ADDR_W);
> > + if (cmd != NAND_CMD_NONE) {
> > + if (ctrl & NAND_CLE) {
> > + gpmc_hwcontrol(1, info->gpmc_cs,
> > + GPMC_NAND_COMMAND, cmd, NULL);
> > +
> > + } else if (ctrl & NAND_ALE) {
> > + gpmc_hwcontrol(1, info->gpmc_cs,
> > + GPMC_NAND_ADDRESS, cmd, NULL);
> > +
> > + } else /* NAND_NCE */
> > + gpmc_hwcontrol(1, info->gpmc_cs,
> > + GPMC_NAND_DATA, cmd, NULL);
> > + }
> > }
> >
> > /**
> > @@ -229,14 +191,15 @@ static void omap_read_buf8(struct mtd_info *mtd,
> u_char *buf, int len)
> > */
> > static void omap_write_buf8(struct mtd_info *mtd, const u_char *buf,
> int len)
> > {
> > - struct omap_nand_info *info = container_of(mtd,
> > - struct omap_nand_info,
> mtd);
> > + u32 status;
> > + struct nand_chip *nand = mtd->priv;
> > u_char *p = (u_char *)buf;
> >
> > while (len--) {
> > - iowrite8(*p++, info->nand.IO_ADDR_W);
> > - while (GPMC_BUF_EMPTY == (readl(info->gpmc_baseaddr +
> > - GPMC_STATUS) &
> GPMC_BUF_FULL));
> > + iowrite8(*p++, nand->IO_ADDR_W);
> > + gpmc_hwcontrol(0, 0, GPMC_GET_SET_STATUS, 0, &status);
> If I am not mistaking, 2nd argument is 'cs', correct? And then, why
> are you hard coding this?
> Different boards will have NAND chip present at different 'cs'.
> Please have a look at uses of 'gpmc_hwcontrol' elsewhere as well for this.
[Ghorai] I agree.
>
> Again, say, you got '(status & GPMC_BUF_FULL) != GPMC_BUF_EMPTY', then:
>
> > + while (GPMC_BUF_EMPTY == (status & GPMC_BUF_FULL))
> > + ;
>
> You got in an infinite loop here?
[Ghorai] if you see carefully this is same as existing code. Let me check if any better solution.
>
> > }
> > }
> >
> > @@ -261,18 +224,17 @@ static void omap_read_buf16(struct mtd_info *mtd,
> u_char *buf, int len)
> > */
> > static void omap_write_buf16(struct mtd_info *mtd, const u_char * buf,
> int len)
> > {
> > - struct omap_nand_info *info = container_of(mtd,
> > - struct omap_nand_info,
> mtd);
> > + u32 status;
> > + struct nand_chip *nand = mtd->priv;
> > u16 *p = (u16 *) buf;
> >
> > /* FIXME try bursts of writesw() or DMA ... */
> > len >>= 1;
> >
> > while (len--) {
> > - iowrite16(*p++, info->nand.IO_ADDR_W);
> > -
> > - while (GPMC_BUF_EMPTY == (readl(info->gpmc_baseaddr +
> > - GPMC_STATUS) &
> GPMC_BUF_FULL))
> > + iowrite16(*p++, nand->IO_ADDR_W);
> > + gpmc_hwcontrol(0, 0, GPMC_GET_SET_STATUS, 0, &status);
> > + while (GPMC_BUF_EMPTY == (status & GPMC_BUF_FULL))
>
> same as above.
[Ghorai] if you see carefully this is same as existing code. Let me check if any better solution.
>
>
> --
> Regards,
> Vimal Singh
WARNING: multiple messages have this Message-ID (diff)
From: "Ghorai, Sukumar" <s-ghorai@ti.com>
To: Vimal Singh <vimal.newwork@gmail.com>
Cc: "tony@atomide.com" <tony@atomide.com>,
"Artem.Bityutskiy@nokia.com" <Artem.Bityutskiy@nokia.com>,
"linux-omap@vger.kernel.org" <linux-omap@vger.kernel.org>,
"sakoman@gmail.com" <sakoman@gmail.com>,
"linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>
Subject: RE: [PATCH v2 1/2] omap3 nand: cleanup for not to use GPMC virtual address
Date: Mon, 17 May 2010 09:52:40 +0530 [thread overview]
Message-ID: <2A3DCF3DA181AD40BDE86A3150B27B6B030D8FB75B@dbde02.ent.ti.com> (raw)
In-Reply-To: <AANLkTinGirx4-PPkpPhYEutbnN_uIPoYbA7BlUPCPnaK@mail.gmail.com>
Vimal,
> -----Original Message-----
> From: Vimal Singh [mailto:vimal.newwork@gmail.com]
> Sent: 2010-05-14 23:33
> To: Ghorai, Sukumar
> Cc: linux-omap@vger.kernel.org; Artem.Bityutskiy@nokia.com;
> tony@atomide.com; sakoman@gmail.com; linux-mtd@lists.infradead.org
> Subject: Re: [PATCH v2 1/2] omap3 nand: cleanup for not to use GPMC
> virtual address
>
> On Fri, May 14, 2010 at 8:53 PM, Sukumar Ghorai <s-ghorai@ti.com> wrote:
> [...]
>
> > diff --git a/arch/arm/mach-omap2/gpmc-onenand.c b/arch/arm/mach-
> omap2/gpmc-onenand.c
> > index 7bb6922..5d66817
> > --- a/arch/arm/mach-omap2/gpmc-onenand.c
> > +++ b/arch/arm/mach-omap2/gpmc-onenand.c
> > @@ -301,7 +301,7 @@ static int omap2_onenand_set_sync_mode(struct
> omap_onenand_platform_data *cfg,
> > (GPMC_CONFIG1_WAIT_READ_MON |
> > GPMC_CONFIG1_WAIT_PIN_SEL(0))) |
> > GPMC_CONFIG1_DEVICESIZE_16 |
> > - GPMC_CONFIG1_DEVICETYPE_NOR |
> > + GPMC_CONFIG1_DEVICETYPE(GPMC_DEVICETYPE_NOR) |
> > GPMC_CONFIG1_MUXADDDATA);
>
> Please do not dp OneNAND changes in NAND patch.
[Ghorai] I agree.
>
> > diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
> > index 5bc3ca0..a3fd1ed
> > --- a/arch/arm/mach-omap2/gpmc.c
> > +++ b/arch/arm/mach-omap2/gpmc.c
> > @@ -29,27 +29,27 @@
> > #include <plat/sdrc.h>
> >
> > /* GPMC register offsets */
> > -#define GPMC_REVISION 0x00
> > -#define GPMC_SYSCONFIG 0x10
> > -#define GPMC_SYSSTATUS 0x14
> > -#define GPMC_IRQSTATUS 0x18
> > -#define GPMC_IRQENABLE 0x1c
> > -#define GPMC_TIMEOUT_CONTROL 0x40
> > -#define GPMC_ERR_ADDRESS 0x44
> > -#define GPMC_ERR_TYPE 0x48
> > -#define GPMC_CONFIG 0x50
> > -#define GPMC_STATUS 0x54
> > -#define GPMC_PREFETCH_CONFIG1 0x1e0
> > -#define GPMC_PREFETCH_CONFIG2 0x1e4
> > -#define GPMC_PREFETCH_CONTROL 0x1ec
> > -#define GPMC_PREFETCH_STATUS 0x1f0
> > -#define GPMC_ECC_CONFIG 0x1f4
> > -#define GPMC_ECC_CONTROL 0x1f8
> > -#define GPMC_ECC_SIZE_CONFIG 0x1fc
> > -
> > -#define GPMC_CS0 0x60
> > -#define GPMC_CS_SIZE 0x30
> > -
> > +#define GPMC_REVISION 0x00
> > +#define GPMC_SYSCONFIG 0x10
> > +#define GPMC_SYSSTATUS 0x14
> > +#define GPMC_IRQSTATUS 0x18
> > +#define GPMC_IRQENABLE 0x1c
> > +#define GPMC_TIMEOUT_CONTROL 0x40
> > +#define GPMC_ERR_ADDRESS 0x44
> > +#define GPMC_ERR_TYPE 0x48
> > +#define GPMC_CONFIG 0x50
> > +#define GPMC_STATUS 0x54
> > +#define GPMC_PREFETCH_CONFIG1 0x1e0
> > +#define GPMC_PREFETCH_CONFIG2 0x1e4
> > +#define GPMC_PREFETCH_CONTROL 0x1ec
> > +#define GPMC_PREFETCH_STATUS 0x1f0
> > +#define GPMC_ECC_CONFIG 0x1f4
> > +#define GPMC_ECC_CONTROL 0x1f8
> > +#define GPMC_ECC_SIZE_CONFIG 0x1fc
> > +#define GPMC_ECC1_RESULT 0x200
> > +
> > +#define GPMC_CS0_BASE 0x60
> > +#define GPMC_CS_SIZE 0x30
> > #define GPMC_MEM_START 0x00000000
> > #define GPMC_MEM_END 0x3FFFFFFF
> > #define BOOT_ROM_SPACE 0x100000 /* 1MB */
> > @@ -108,11 +108,27 @@ static u32 gpmc_read_reg(int idx)
> > return __raw_readl(gpmc_base + idx);
> > }
> >
> > +static void gpmc_cs_write_byte(int cs, int idx, u8 val)
> > +{
> > + void __iomem *reg_addr;
> > +
> > + reg_addr = gpmc_base + GPMC_CS0_BASE + (cs * GPMC_CS_SIZE) +
> idx;
> > + __raw_writeb(val, reg_addr);
> > +}
> > +
> > +static u8 gpmc_cs_read_byte(int cs, int idx)
> > +{
> > + void __iomem *reg_addr;
> > +
> > + reg_addr = gpmc_base + GPMC_CS0_BASE + (cs * GPMC_CS_SIZE) +
> idx;
> > + return __raw_readb(reg_addr);
> > +}
> > +
>
> I do not think we need these functions.
[Ghorai] This is used in gpmc_hwcontrol() and to get the nand status from omap2.c.
>
> > void gpmc_cs_write_reg(int cs, int idx, u32 val)
> > {
> > void __iomem *reg_addr;
> >
> > - reg_addr = gpmc_base + GPMC_CS0 + (cs * GPMC_CS_SIZE) + idx;
> > + reg_addr = gpmc_base + GPMC_CS0_BASE + (cs * GPMC_CS_SIZE) +
> idx;
> > __raw_writel(val, reg_addr);
> > }
> >
> > @@ -120,7 +136,7 @@ u32 gpmc_cs_read_reg(int cs, int idx)
> > {
> > void __iomem *reg_addr;
> >
> > - reg_addr = gpmc_base + GPMC_CS0 + (cs * GPMC_CS_SIZE) + idx;
> > + reg_addr = gpmc_base + GPMC_CS0_BASE + (cs * GPMC_CS_SIZE) +
> idx;
> > return __raw_readl(reg_addr);
> > }
> >
> > @@ -419,6 +435,96 @@ void gpmc_cs_free(int cs)
> > EXPORT_SYMBOL(gpmc_cs_free);
> >
> > /**
> > + * gpmc_hwcontrol - hardware specific access (read/ write) to control
> > + * @write: need 1 for configure; 0 for reading the complete register
> > + * @cs: chip select number
> > + * @cmd: Command type
> > + * @wval: value/information to write
> > + * @rval: pointer to get the value back
> > + */
> > +int gpmc_hwcontrol(int write, int cs, int cmd, int wval, int *rval)
> > +{
> > + u32 reg = 0;
> > + u32 regval = 0;
> > +
> > + switch (cmd) {
> > +
> > + case GPMC_GET_SET_STATUS:
> > + reg = GPMC_STATUS;
> > + if (write)
> > + gpmc_write_reg(GPMC_STATUS, regval);
> > + break;
> > +
> > + case GPMC_GET_SET_IRQ_STATUS:
> > + reg = GPMC_IRQSTATUS;
> > + if (write)
> > + gpmc_write_reg(GPMC_IRQSTATUS, regval);
> > + break;
> > +
> > + case GPMC_GET_PREF_STATUS:
> > + reg = GPMC_PREFETCH_STATUS;
> > + break;
> > +
> > + case GPMC_CONFIG_WP:
> > + reg = GPMC_CONFIG;
> > + regval = gpmc_read_reg(GPMC_CONFIG);
> > + if (wval)
> > + regval &= ~GPMC_CONFIG_WRITEPROTECT; /* WP is ON
> */
> > + else
> > + regval |= GPMC_CONFIG_WRITEPROTECT; /* WP is
> OFF */
> > + gpmc_write_reg(reg, regval);
> > + break;
> > +
> > + case GPMC_CONFIG_RDY_BSY:
> > + #define WR_RD_PIN_MONITORING 0x00600000
> > + regval = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
> > + regval |= WR_RD_PIN_MONITORING;
> > + gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, regval);
> > + break;
> > +
> > + case GPMC_CONFIG_DEV_SIZE:
> > + regval = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
> > + regval |= GPMC_CONFIG1_DEVICESIZE(wval);
> > + gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, regval);
> > + break;
> > +
> > + case GPMC_CONFIG_DEV_TYPE:
> > + regval = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
> > + regval |= GPMC_CONFIG1_DEVICETYPE(wval);
> > + if (wval == GPMC_DEVICETYPE_NOR)
> > + regval |= GPMC_CONFIG1_MUXADDDATA;
> > + gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, regval);
> > + break;
> > +
> > + case GPMC_NAND_COMMAND:
> > + gpmc_cs_write_byte(cs, GPMC_CS_NAND_COMMAND, wval);
> > + break;
> > +
> > + case GPMC_NAND_ADDRESS:
> > + gpmc_cs_write_byte(cs, GPMC_CS_NAND_ADDRESS, wval);
> > + break;
> > +
> > + case GPMC_NAND_DATA:
> > + if (write)
> > + gpmc_cs_write_byte(cs, GPMC_CS_NAND_DATA, wval);
> > + else
> > + *rval = gpmc_cs_read_byte(cs,
> GPMC_CS_NAND_DATA);
> > + break;
> > +
> > + default:
> > + dump_stack();
> > + printk(KERN_ERR "not supported\n");
> > + return -1;
> > + }
> > +
> > + if (!write && reg)
> > + *rval = gpmc_read_reg(reg);
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(gpmc_hwcontrol);
> > +
> > +/**
> > * gpmc_prefetch_enable - configures and starts prefetch transfer
> > * @cs: nand cs (chip select) number
> > * @dma_mode: dma mode enable (1) or disable (0)
> > @@ -466,15 +572,6 @@ void gpmc_prefetch_reset(void)
> > }
> > EXPORT_SYMBOL(gpmc_prefetch_reset);
> >
> > -/**
> > - * gpmc_prefetch_status - reads prefetch status of engine
> > - */
> > -int gpmc_prefetch_status(void)
> > -{
> > - return gpmc_read_reg(GPMC_PREFETCH_STATUS);
> > -}
> > -EXPORT_SYMBOL(gpmc_prefetch_status);
> > -
> > static void __init gpmc_mem_init(void)
> > {
> > int cs;
> > @@ -615,3 +712,86 @@ void omap3_gpmc_restore_context(void)
> > }
> > }
> > #endif /* CONFIG_ARCH_OMAP3 */
> > +
> > +/**
> > + * gmpc_ecc_init - Initialize the HW ECC for NAND flash in GPMC
> controller
> > + * @cs: Chip select number
> > + * @ecc_size: bytes for which ECC will be generated
> > + */
> > +void gpmc_ecc_init(int cs, int ecc_size)
> > +{
> > + unsigned int val = 0x0;
> > +
> > + /* Read from ECC Control Register */
> > + val = gpmc_read_reg(GPMC_ECC_CONTROL);
> > +
> > + /* Clear all ECC | Enable Reg1 */
> > + val = ((0x00000001<<8) | 0x00000001);
> > + gpmc_write_reg(GPMC_ECC_CONTROL, val);
> > +
> > + /* Read from ECC Size Config Register */
> > + val = gpmc_read_reg(GPMC_ECC_SIZE_CONFIG);
> > + /* ECCSIZE1=512 | Select eccResultsize[0-3] */
> > + val = ((((ecc_size >> 1) - 1) << 22) | (0x0000000F));
> > + gpmc_write_reg(GPMC_ECC_SIZE_CONFIG, val);
> > +}
> > +
> > +/**
> > + * gpmc_calcuate_ecc - Generate non-inverted ECC bytes.
> > + * @cs: Chip select number
> > + * @dat: The pointer to data on which ecc is computed
> > + * @ecc_code: The ecc_code buffer
> > + *
> > + * Using noninverted ECC can be considered ugly since writing a blank
> > + * page ie. padding will clear the ECC bytes. This is no problem as
> long
> > + * nobody is trying to write data on the seemingly unused page. Reading
> > + * an erased page will produce an ECC mismatch between generated and
> read
> > + * ECC bytes that has to be dealt with separately.
> > + */
> > +int gpmc_calculate_ecc(int cs, const u_char *dat, u_char *ecc_code)
> > +{
> > + unsigned int val = 0x0;
> > +
> > + /* Start Reading from HW ECC1_Result = 0x200 */
> > + val = gpmc_read_reg(GPMC_ECC1_RESULT);
> > + *ecc_code++ = val; /* P128e, ..., P1e */
> > + *ecc_code++ = val >> 16; /* P128o, ..., P1o */
> > + /* P2048o, P1024o, P512o, P256o, P2048e, P1024e, P512e, P256e */
> > + *ecc_code++ = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0);
> > +
> > + return 0;
> > +}
> > +
> > +/**
> > + * gpmc_enable_hwecc - This function enables the hardware ecc
> functionality
> > + * @cs: Chip select number
> > + * @mode: Read/Write mode
> > + * @dev_width: device bus width
> > + */
> > +void gpmc_enable_hwecc(int cs, int mode, int dev_width)
> > +{
> > + unsigned int val = gpmc_read_reg(GPMC_ECC_CONFIG);
> > +
> > + switch (mode) {
> > + case GPMC_ECC_READ:
> > + gpmc_write_reg(GPMC_ECC_CONTROL, 0x101);
> > + /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
> > + val = (dev_width << 7) | (cs << 1) | (0x1);
> > + break;
> > + case GPMC_ECC_READSYN:
> > + gpmc_write_reg(GPMC_ECC_CONTROL, 0x100);
> > + /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
> > + val = (dev_width << 7) | (cs << 1) | (0x1);
> > + break;
> > + case GPMC_ECC_WRITE:
> > + gpmc_write_reg(GPMC_ECC_CONTROL, 0x101);
> > + /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
> > + val = (dev_width << 7) | (cs << 1) | (0x1);
> > + break;
> > + default:
> > + printk(KERN_INFO "Error: Unrecognized Mode[%d]!\n",
> mode);
> > + break;
> > + }
> > +
> > + gpmc_write_reg(GPMC_ECC_CONFIG, val);
> > +}
> > diff --git a/arch/arm/plat-omap/include/plat/gpmc.h b/arch/arm/plat-
> omap/include/plat/gpmc.h
> > index 145838a..56e1407
> > --- a/arch/arm/plat-omap/include/plat/gpmc.h
> > +++ b/arch/arm/plat-omap/include/plat/gpmc.h
> > @@ -25,10 +25,22 @@
> > #define GPMC_CS_NAND_ADDRESS 0x20
> > #define GPMC_CS_NAND_DATA 0x24
> >
> > -#define GPMC_CONFIG 0x50
> > -#define GPMC_STATUS 0x54
> > -#define GPMC_CS0_BASE 0x60
> > -#define GPMC_CS_SIZE 0x30
> > +/* Control Commands */
> > +#define GPMC_GET_SET_STATUS 0x00000001
> > +#define GPMC_CONFIG_WP 0x00000002
> > +#define GPMC_CONFIG_RDY_BSY 0x00000003
> > +#define GPMC_CONFIG_DEV_SIZE 0x00000004
> > +#define GPMC_CONFIG_DEV_TYPE 0x00000005
> > +#define GPMC_NAND_COMMAND 0x00000006
> > +#define GPMC_NAND_ADDRESS 0x00000007
> > +#define GPMC_NAND_DATA 0x00000008
> > +#define GPMC_GET_PREF_STATUS 0x00000009
> > +#define GPMC_GET_SET_IRQ_STATUS 0x0000000a
> > +
> > +/* ECC commands */
> > +#define GPMC_ECC_READ 0 /* Reset Hardware ECC for read */
> > +#define GPMC_ECC_WRITE 1 /* Reset Hardware ECC for write */
> > +#define GPMC_ECC_READSYN 2 /* Reset before syndrom is read back
> */
> >
> > #define GPMC_CONFIG1_WRAPBURST_SUPP (1 << 31)
> > #define GPMC_CONFIG1_READMULTIPLE_SUPP (1 << 30)
> > @@ -44,10 +56,7 @@
> > #define GPMC_CONFIG1_WAIT_MON_IIME(val) ((val & 3) << 18)
> > #define GPMC_CONFIG1_WAIT_PIN_SEL(val) ((val & 3) << 16)
> > #define GPMC_CONFIG1_DEVICESIZE(val) ((val & 3) << 12)
> > -#define GPMC_CONFIG1_DEVICESIZE_16 GPMC_CONFIG1_DEVICESIZE(1)
> > #define GPMC_CONFIG1_DEVICETYPE(val) ((val & 3) << 10)
> > -#define GPMC_CONFIG1_DEVICETYPE_NOR GPMC_CONFIG1_DEVICETYPE(0)
> > -#define GPMC_CONFIG1_DEVICETYPE_NAND GPMC_CONFIG1_DEVICETYPE(2)
> > #define GPMC_CONFIG1_MUXADDDATA (1 << 9)
> > #define GPMC_CONFIG1_TIME_PARA_GRAN (1 << 4)
> > #define GPMC_CONFIG1_FCLK_DIV(val) (val & 3)
> > @@ -56,6 +65,12 @@
> > #define GPMC_CONFIG1_FCLK_DIV4 (GPMC_CONFIG1_FCLK_DIV(3))
> > #define GPMC_CONFIG7_CSVALID (1 << 6)
> >
> > +#define GPMC_DEVICETYPE_NOR 0
> > +#define GPMC_DEVICETYPE_NAND 2
> > +#define GPMC_CONFIG_WRITEPROTECT 0x00000010
> > +#define GPMC_CONFIG1_DEVICESIZE_16 GPMC_CONFIG1_DEVICESIZE(1)
> > +
> > +
> > /*
> > * Note that all values in this struct are in nanoseconds, while
> > * the register values are in gpmc_fck cycles.
> > @@ -109,9 +124,14 @@ extern int gpmc_cs_reserved(int cs);
> > extern int gpmc_prefetch_enable(int cs, int dma_mode,
> > unsigned int u32_count, int
> is_write);
> > extern void gpmc_prefetch_reset(void);
> > -extern int gpmc_prefetch_status(void);
> > extern void omap3_gpmc_save_context(void);
> > extern void omap3_gpmc_restore_context(void);
> > extern void gpmc_init(void);
> > +extern int gpmc_hwcontrol(int write, int cs, int cmd, int wval, int
> *rval);
> > +
> > +void gpmc_ecc_init(int cs, int ecc_size);
> > +void gpmc_enable_hwecc(int cs, int mode, int dev_width);
> > +int gpmc_calculate_ecc(int cs, const u_char *dat, u_char *ecc_code);
> > +
> >
> > #endif
> > diff --git a/arch/arm/plat-omap/include/plat/nand.h b/arch/arm/plat-
> omap/include/plat/nand.h
> > index f8efd54..6562cd0
> > --- a/arch/arm/plat-omap/include/plat/nand.h
> > +++ b/arch/arm/plat-omap/include/plat/nand.h
> > @@ -21,13 +21,11 @@ struct omap_nand_platform_data {
> > int (*dev_ready)(struct
> omap_nand_platform_data *);
> > int dma_channel;
> > unsigned long phys_base;
> > - void __iomem *gpmc_cs_baseaddr;
> > - void __iomem *gpmc_baseaddr;
> > int devsize;
> > };
> >
> > -/* size (4 KiB) for IO mapping */
> > -#define NAND_IO_SIZE SZ_4K
> > +/* minimum size for IO mapping */
> > +#define NAND_IO_SIZE 4
> >
> > #if defined(CONFIG_MTD_NAND_OMAP2) ||
> defined(CONFIG_MTD_NAND_OMAP2_MODULE)
> > extern int gpmc_nand_init(struct omap_nand_platform_data *d);
> > diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
> > index 7545568..1858c42
> > --- a/drivers/mtd/nand/omap2.c
> > +++ b/drivers/mtd/nand/omap2.c
> > @@ -23,12 +23,6 @@
> > #include <plat/gpmc.h>
> > #include <plat/nand.h>
> >
> > -#define GPMC_IRQ_STATUS 0x18
> > -#define GPMC_ECC_CONFIG 0x1F4
> > -#define GPMC_ECC_CONTROL 0x1F8
> > -#define GPMC_ECC_SIZE_CONFIG 0x1FC
> > -#define GPMC_ECC1_RESULT 0x200
> > -
> > #define DRIVER_NAME "omap2-nand"
> >
> > #define NAND_WP_OFF 0
> > @@ -37,6 +31,7 @@
> > #define GPMC_BUF_FULL 0x00000001
> > #define GPMC_BUF_EMPTY 0x00000000
> >
> > +#ifdef CONFIG_MTD_NAND_OMAP_HWECC
> > #define NAND_Ecc_P1e (1 << 0)
> > #define NAND_Ecc_P2e (1 << 1)
> > #define NAND_Ecc_P4e (1 << 2)
> > @@ -103,6 +98,7 @@
> >
> > #define P4e_s(a) (TF(a & NAND_Ecc_P4e) << 0)
> > #define P4o_s(a) (TF(a & NAND_Ecc_P4o) << 1)
> > +#endif /* CONFIG_MTD_NAND_OMAP_HWECC */
>
> Why this ifdef macro?
>
> >
> > #ifdef CONFIG_MTD_PARTITIONS
> > static const char *part_probes[] = { "cmdlinepart", NULL };
> > @@ -139,34 +135,11 @@ struct omap_nand_info {
> >
> > int gpmc_cs;
> > unsigned long phys_base;
> > - void __iomem *gpmc_cs_baseaddr;
> > - void __iomem *gpmc_baseaddr;
> > - void __iomem *nand_pref_fifo_add;
> > struct completion comp;
> > int dma_ch;
> > };
> >
> > /**
> > - * omap_nand_wp - This function enable or disable the Write Protect
> feature
> > - * @mtd: MTD device structure
> > - * @mode: WP ON/OFF
> > - */
> > -static void omap_nand_wp(struct mtd_info *mtd, int mode)
> > -{
> > - struct omap_nand_info *info = container_of(mtd,
> > - struct omap_nand_info,
> mtd);
> > -
> > - unsigned long config = __raw_readl(info->gpmc_baseaddr +
> GPMC_CONFIG);
> > -
> > - if (mode)
> > - config &= ~(NAND_WP_BIT); /* WP is ON */
> > - else
> > - config |= (NAND_WP_BIT); /* WP is OFF */
> > -
> > - __raw_writel(config, (info->gpmc_baseaddr + GPMC_CONFIG));
> > -}
> > -
> > -/**
> > * omap_hwcontrol - hardware specific access to control-lines
> > * @mtd: MTD device structure
> > * @cmd: command to device
> > @@ -181,31 +154,20 @@ static void omap_hwcontrol(struct mtd_info *mtd,
> int cmd, unsigned int ctrl)
> > {
> > struct omap_nand_info *info = container_of(mtd,
> > struct omap_nand_info, mtd);
> > - switch (ctrl) {
> > - case NAND_CTRL_CHANGE | NAND_CTRL_CLE:
> > - info->nand.IO_ADDR_W = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_COMMAND;
> > - info->nand.IO_ADDR_R = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_DATA;
> > - break;
> > -
> > - case NAND_CTRL_CHANGE | NAND_CTRL_ALE:
> > - info->nand.IO_ADDR_W = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_ADDRESS;
> > - info->nand.IO_ADDR_R = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_DATA;
> > - break;
> > -
> > - case NAND_CTRL_CHANGE | NAND_NCE:
> > - info->nand.IO_ADDR_W = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_DATA;
> > - info->nand.IO_ADDR_R = info->gpmc_cs_baseaddr +
> > - GPMC_CS_NAND_DATA;
> > - break;
> > - }
> >
> > - if (cmd != NAND_CMD_NONE)
> > - __raw_writeb(cmd, info->nand.IO_ADDR_W);
> > + if (cmd != NAND_CMD_NONE) {
> > + if (ctrl & NAND_CLE) {
> > + gpmc_hwcontrol(1, info->gpmc_cs,
> > + GPMC_NAND_COMMAND, cmd, NULL);
> > +
> > + } else if (ctrl & NAND_ALE) {
> > + gpmc_hwcontrol(1, info->gpmc_cs,
> > + GPMC_NAND_ADDRESS, cmd, NULL);
> > +
> > + } else /* NAND_NCE */
> > + gpmc_hwcontrol(1, info->gpmc_cs,
> > + GPMC_NAND_DATA, cmd, NULL);
> > + }
> > }
> >
> > /**
> > @@ -229,14 +191,15 @@ static void omap_read_buf8(struct mtd_info *mtd,
> u_char *buf, int len)
> > */
> > static void omap_write_buf8(struct mtd_info *mtd, const u_char *buf,
> int len)
> > {
> > - struct omap_nand_info *info = container_of(mtd,
> > - struct omap_nand_info,
> mtd);
> > + u32 status;
> > + struct nand_chip *nand = mtd->priv;
> > u_char *p = (u_char *)buf;
> >
> > while (len--) {
> > - iowrite8(*p++, info->nand.IO_ADDR_W);
> > - while (GPMC_BUF_EMPTY == (readl(info->gpmc_baseaddr +
> > - GPMC_STATUS) &
> GPMC_BUF_FULL));
> > + iowrite8(*p++, nand->IO_ADDR_W);
> > + gpmc_hwcontrol(0, 0, GPMC_GET_SET_STATUS, 0, &status);
> If I am not mistaking, 2nd argument is 'cs', correct? And then, why
> are you hard coding this?
> Different boards will have NAND chip present at different 'cs'.
> Please have a look at uses of 'gpmc_hwcontrol' elsewhere as well for this.
[Ghorai] I agree.
>
> Again, say, you got '(status & GPMC_BUF_FULL) != GPMC_BUF_EMPTY', then:
>
> > + while (GPMC_BUF_EMPTY == (status & GPMC_BUF_FULL))
> > + ;
>
> You got in an infinite loop here?
[Ghorai] if you see carefully this is same as existing code. Let me check if any better solution.
>
> > }
> > }
> >
> > @@ -261,18 +224,17 @@ static void omap_read_buf16(struct mtd_info *mtd,
> u_char *buf, int len)
> > */
> > static void omap_write_buf16(struct mtd_info *mtd, const u_char * buf,
> int len)
> > {
> > - struct omap_nand_info *info = container_of(mtd,
> > - struct omap_nand_info,
> mtd);
> > + u32 status;
> > + struct nand_chip *nand = mtd->priv;
> > u16 *p = (u16 *) buf;
> >
> > /* FIXME try bursts of writesw() or DMA ... */
> > len >>= 1;
> >
> > while (len--) {
> > - iowrite16(*p++, info->nand.IO_ADDR_W);
> > -
> > - while (GPMC_BUF_EMPTY == (readl(info->gpmc_baseaddr +
> > - GPMC_STATUS) &
> GPMC_BUF_FULL))
> > + iowrite16(*p++, nand->IO_ADDR_W);
> > + gpmc_hwcontrol(0, 0, GPMC_GET_SET_STATUS, 0, &status);
> > + while (GPMC_BUF_EMPTY == (status & GPMC_BUF_FULL))
>
> same as above.
[Ghorai] if you see carefully this is same as existing code. Let me check if any better solution.
>
>
> --
> Regards,
> Vimal Singh
next prev parent reply other threads:[~2010-05-17 4:22 UTC|newest]
Thread overview: 159+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <Sukumar Ghorai <s-ghorai@ti.com>
2010-04-06 12:29 ` [PATCH 0/2] OMAP: Flash device support 3630 sdp board Sukumar Ghorai
2010-04-06 12:29 ` [PATCH 1/2] OMAP3630SDP: Add support for Flash Sukumar Ghorai
2010-04-06 12:29 ` [PATCH 2/2] OMAP3630SDP: enable Flash device support Sukumar Ghorai
2010-04-06 13:02 ` [PATCH 1/2] OMAP3630SDP: Add support for Flash Vimal Singh
2010-04-13 17:37 ` [PATCH] nand support on omap3 boards Sukumar Ghorai
2010-04-13 17:37 ` [PATCH v3 1/8] omap3: zoom: Introducing 'board-zoom-flash.c' Sukumar Ghorai
2010-04-13 17:37 ` [PATCH v3 2/8] omap3: add support for NAND on zoom2 board Sukumar Ghorai
2010-04-13 17:37 ` [PATCH v3 3/8] omap3: add support for NAND on zoom3 board Sukumar Ghorai
2010-04-13 17:37 ` [PATCH v2 4/8] omap-3630-sdp : Add support for Flash Sukumar Ghorai
2010-04-13 17:37 ` [PATCH v2 5/8] omap-3630-sdp: enable Flash device support Sukumar Ghorai
2010-04-13 17:37 ` [PATCH v2 6/8] omap3: add support for NAND on LDP board Sukumar Ghorai
2010-04-13 17:37 ` [PATCH 7/8] zoom2: enable NAND support Sukumar Ghorai
2010-04-13 17:37 ` [PATCH 8/8] zoom3: " Sukumar Ghorai
2010-04-13 17:37 ` [PATCH] nand support on omap3 boards Sukumar Ghorai
2010-04-13 17:37 ` [PATCH 8/8] omap3: GPMC register definition at common location Sukumar Ghorai
2010-04-13 17:37 ` [PATCH] omap3: NAND Prefetch in IRQ mode support Sukumar Ghorai
2010-04-13 17:37 ` [PATCH] omap-3630 NAND: enable NAND io in prefetch-irq mode Sukumar Ghorai
2010-04-13 17:37 ` [PATCH] omap: NAND: ecc layout select from board file Sukumar Ghorai
2010-04-13 17:37 ` [PATCH] omap: NAND: Making ecc layout as compatible with romcode ecc Sukumar Ghorai
2010-04-14 4:35 ` [PATCH] nand support on omap3 boards Vimal Singh
2010-04-14 4:37 ` Vimal Singh
2010-04-14 4:38 ` Ghorai, Sukumar
2010-05-04 6:00 ` Ghorai, Sukumar
2010-05-04 6:01 ` Ghorai, Sukumar
2010-05-28 13:48 ` Ghorai, Sukumar
2010-04-13 17:44 ` Sukumar Ghorai
2010-04-16 11:32 ` [PATCH 0/6] nand prefetch-irq support and ecc layout chanage Sukumar Ghorai
2010-04-16 11:32 ` Sukumar Ghorai
2010-04-16 11:34 ` [PATCH 1/6] omap3: GPMC register definition at common location Sukumar Ghorai
2010-04-16 11:34 ` Sukumar Ghorai
2010-04-16 11:35 ` [PATCH 2/6] omap3: NAND Prefetch in IRQ mode support Sukumar Ghorai
2010-04-16 11:35 ` Sukumar Ghorai
2010-04-16 11:35 ` [PATCH 3/6] OMAP NAND: configurable fifo threshold to gain the throughput Sukumar Ghorai
2010-04-16 11:35 ` Sukumar Ghorai
2010-04-16 12:45 ` Vimal Singh
2010-04-16 12:45 ` Vimal Singh
2010-04-16 11:35 ` [PATCH 4/6] omap-3630 NAND: enable NAND io in prefetch-irq mode Sukumar Ghorai
2010-04-16 11:35 ` Sukumar Ghorai
2010-04-16 11:35 ` [PATCH 5/6] omap: NAND: ecc layout select from board file Sukumar Ghorai
2010-04-16 11:35 ` Sukumar Ghorai
2010-04-16 11:35 ` [PATCH 6/6] omap: NAND: Making ecc layout as compatible with romcode ecc Sukumar Ghorai
2010-04-16 11:35 ` Sukumar Ghorai
2010-05-12 9:48 ` [PATCH 0/3] omap3 nand: cleanup exiting platform related code Sukumar Ghorai
2010-05-12 9:48 ` Sukumar Ghorai
2010-05-12 9:48 ` [PATCH 1/3] omap3: GPMC register definition at common location Sukumar Ghorai
2010-05-12 9:48 ` Sukumar Ghorai
2010-05-12 9:48 ` [PATCH 2/3] omap3 nand: cleanup for not to use GPMC virtual address Sukumar Ghorai
2010-05-12 9:48 ` Sukumar Ghorai
2010-05-12 9:48 ` [PATCH 3/3] omap3 nand: fix issue in board file to detect the nand Sukumar Ghorai
2010-05-12 9:48 ` Sukumar Ghorai
2010-05-13 15:41 ` [PATCH 2/3] omap3 nand: cleanup for not to use GPMC virtual address Tony Lindgren
2010-05-13 15:41 ` Tony Lindgren
2010-05-13 18:48 ` Ghorai, Sukumar
2010-05-13 18:48 ` Ghorai, Sukumar
2010-05-13 6:15 ` [PATCH 1/3] omap3: GPMC register definition at common location Mike Rapoport
2010-05-13 6:15 ` Mike Rapoport
2010-05-13 15:41 ` Tony Lindgren
2010-05-13 15:41 ` Tony Lindgren
2010-05-13 15:44 ` [PATCH 0/3] omap3 nand: cleanup exiting platform related code Tony Lindgren
2010-05-13 15:44 ` Tony Lindgren
2010-05-14 15:23 ` [PATCH v2 0/2] " Sukumar Ghorai
2010-05-14 15:23 ` Sukumar Ghorai
2010-05-14 15:23 ` [PATCH v2 1/2] omap3 nand: cleanup for not to use GPMC virtual address Sukumar Ghorai
2010-05-14 15:23 ` Sukumar Ghorai
2010-05-14 15:23 ` [PATCH v2 2/2] omap3 nand: fix issue in board file to detect the nand Sukumar Ghorai
2010-05-14 15:23 ` Sukumar Ghorai
2010-05-14 15:28 ` [PATCH v2 1/2] omap3 nand: cleanup for not to use GPMC virtual address Tony Lindgren
2010-05-14 15:28 ` Tony Lindgren
2010-05-14 18:02 ` Vimal Singh
2010-05-14 18:02 ` Vimal Singh
2010-05-17 4:22 ` Ghorai, Sukumar [this message]
2010-05-17 4:22 ` Ghorai, Sukumar
2010-05-17 14:26 ` Vimal Singh
2010-05-17 14:26 ` Vimal Singh
2010-05-17 14:34 ` Ghorai, Sukumar
2010-05-17 14:34 ` Ghorai, Sukumar
2010-05-14 23:58 ` Tony Lindgren
2010-05-14 23:58 ` Tony Lindgren
2010-05-17 5:48 ` Ghorai, Sukumar
2010-05-17 5:48 ` Ghorai, Sukumar
2010-05-18 11:16 ` [PATCH v3 0/3] omap3 nand: cleanup exiting platform related code Sukumar Ghorai
2010-05-18 11:16 ` Sukumar Ghorai
2010-05-18 11:16 ` [PATCH v3 1/3] omap3 gpmc: functionality enhancement Sukumar Ghorai
2010-05-18 11:16 ` Sukumar Ghorai
2010-05-18 11:16 ` [PATCH v3 2/3] omap3 nand: cleanup virtual address usages Sukumar Ghorai
2010-05-18 11:16 ` Sukumar Ghorai
2010-05-18 11:16 ` [PATCH v3 3/3] omap3 nand: fix issue in board file to detect nand Sukumar Ghorai
2010-05-18 11:16 ` Sukumar Ghorai
2010-05-19 15:30 ` [PATCH v3 2/3] omap3 nand: cleanup virtual address usages Vimal Singh
2010-05-19 15:30 ` Vimal Singh
2010-05-19 17:24 ` Ghorai, Sukumar
2010-05-19 17:24 ` Ghorai, Sukumar
2010-05-19 18:07 ` Vimal Singh
2010-05-19 18:07 ` Vimal Singh
2010-05-19 18:19 ` Tony Lindgren
2010-05-19 18:19 ` Tony Lindgren
2010-05-19 14:46 ` [PATCH v3 1/3] omap3 gpmc: functionality enhancement Vimal Singh
2010-05-19 14:46 ` Vimal Singh
2010-05-19 15:14 ` Peter Barada
2010-05-19 15:14 ` Peter Barada
2010-05-19 15:48 ` Peter Barada
2010-05-19 15:48 ` Peter Barada
2010-05-19 18:04 ` Ghorai, Sukumar
2010-05-19 18:04 ` Ghorai, Sukumar
2010-05-19 18:30 ` Vimal Singh
2010-05-19 18:30 ` Vimal Singh
2010-05-20 5:38 ` Ghorai, Sukumar
2010-05-20 5:38 ` Ghorai, Sukumar
2010-05-20 14:34 ` Vimal Singh
2010-05-20 14:34 ` Vimal Singh
2010-05-25 14:37 ` Ghorai, Sukumar
2010-05-25 14:37 ` Ghorai, Sukumar
2010-05-25 15:34 ` Vimal Singh
2010-05-25 15:34 ` Vimal Singh
2010-05-27 13:24 ` [PATCH v4 0/3] omap3 nand: cleanup exiting platform related code Sukumar Ghorai
2010-05-27 13:24 ` [PATCH v4 1/3] omap3 gpmc: functionality enhancement Sukumar Ghorai
2010-05-27 13:24 ` [PATCH v4 2/3] omap3 nand: cleanup virtual address usages Sukumar Ghorai
2010-05-27 13:24 ` [PATCH v4 3/3] omap3 nand: fix issue in board file to detect nand Sukumar Ghorai
2010-05-27 18:26 ` [PATCH v4 1/3] omap3 gpmc: functionality enhancement Vimal Singh
2010-06-04 7:40 ` [PATCH v5 0/3] omap3 nand: cleanup exiting platform related code Sukumar Ghorai
2010-06-04 7:40 ` Sukumar Ghorai
2010-06-04 7:40 ` [PATCH v5 1/3] omap3 gpmc: functionality enhancement Sukumar Ghorai
2010-06-04 7:40 ` Sukumar Ghorai
2010-06-04 7:40 ` [PATCH v5 2/3] omap3 nand: cleanup virtual address usages Sukumar Ghorai
2010-06-04 7:40 ` Sukumar Ghorai
2010-06-04 7:40 ` [PATCH v5 3/3] omap3 nand: fix issue in board file to detect nand Sukumar Ghorai
2010-06-04 7:40 ` Sukumar Ghorai
2010-07-07 10:21 ` [PATCH v5 2/3] omap3 nand: cleanup virtual address usages Tony Lindgren
2010-07-07 10:21 ` Tony Lindgren
2010-07-07 12:22 ` Ghorai, Sukumar
2010-07-07 12:22 ` Ghorai, Sukumar
2010-07-07 10:18 ` [PATCH v5 1/3] omap3 gpmc: functionality enhancement Tony Lindgren
2010-07-07 10:18 ` Tony Lindgren
2010-07-07 12:32 ` Ghorai, Sukumar
2010-07-07 12:32 ` Ghorai, Sukumar
2010-07-07 13:01 ` Tony Lindgren
2010-07-07 13:01 ` Tony Lindgren
2010-07-08 3:54 ` Ghorai, Sukumar
2010-07-08 3:54 ` Ghorai, Sukumar
2010-06-08 17:12 ` [PATCH v5 0/3] omap3 nand: cleanup exiting platform related code Vimal Singh
2010-06-08 17:12 ` Vimal Singh
2010-06-15 13:26 ` Ghorai, Sukumar
2010-06-15 13:26 ` Ghorai, Sukumar
2010-06-30 14:42 ` Ghorai, Sukumar
2010-06-30 14:42 ` Ghorai, Sukumar
2010-06-16 11:39 ` [PATCH v3 0/8] nand support on omap3 boards Sukumar Ghorai
2010-06-16 11:39 ` [PATCH v3 1/8] omap3 flash: rename board-sdp-flash.c to be use by other boards Sukumar Ghorai
2010-06-16 11:39 ` [PATCH v3 2/8] omap3: add support for NAND on zoom2 board Sukumar Ghorai
2010-06-16 11:39 ` [PATCH v3 3/8] omap3: add support for NAND on zoom3 board Sukumar Ghorai
2010-06-16 11:39 ` [PATCH v3 4/8] omap-3630-sdp : Add support for Flash Sukumar Ghorai
2010-06-16 11:39 ` [PATCH v3 5/8] omap3: add support for NAND on LDP board Sukumar Ghorai
2010-06-16 11:39 ` [PATCH v3 6/8] omap-3630-sdp: enable Flash device support Sukumar Ghorai
2010-06-16 11:39 ` [PATCH v3 7/8] zoom2: enable NAND support Sukumar Ghorai
2010-06-16 11:40 ` [PATCH v3 8/8] zoom3: " Sukumar Ghorai
2010-07-05 12:27 ` [PATCH v3 6/8] omap-3630-sdp: enable Flash device support Tony Lindgren
2010-07-06 5:23 ` Ghorai, Sukumar
2010-07-05 12:23 ` [PATCH v3 1/8] omap3 flash: rename board-sdp-flash.c to be use by other boards Tony Lindgren
2010-07-06 6:05 ` Shilimkar, Santosh
2010-07-06 6:27 ` Ghorai, Sukumar
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