[PATCH v5 10/14] ARM: OMAP2+: gpmc: waitpin helper
Jon Hunter
jon-hunter at ti.com
Mon Jun 11 18:59:09 EDT 2012
On 06/11/2012 09:27 AM, Afzal Mohammed wrote:
> Helper for configuring waitpin. There are two parts to it;
> configuring at CS level and the other at device level.
> A device embedding multiple CS has been provided the
> capability to use same waitpin (different waitpins has not
> been supported as presently there are no GPMC peripherals
> doing so)
>
> Signed-off-by: Afzal Mohammed <afzal at ti.com>
> ---
> arch/arm/mach-omap2/gpmc.c | 122 ++++++++++++++++++++++++++++++++
> arch/arm/plat-omap/include/plat/gpmc.h | 9 +++
> 2 files changed, 131 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
> index 5a6f708..9073a8a 100644
> --- a/arch/arm/mach-omap2/gpmc.c
> +++ b/arch/arm/mach-omap2/gpmc.c
> @@ -75,6 +75,8 @@
> #define GPMC_CONFIG6_CYCLE2CYCLEDIFFCSEN BIT(6)
> #define GPMC_CONFIG6_CYCLE2CYCLESAMECSEN BIT(7)
>
> +#define GPMC_CONFIG_WAITPIN_POLARITY_SHIFT 0x8
> +
> #define GPMC_CS0_OFFSET 0x60
> #define GPMC_CS_SIZE 0x30
>
> @@ -93,6 +95,19 @@
> */
> #define GPMC_NR_IRQ 2
>
> +enum {
> + GPMC_WAITPIN_IDX0,
> + GPMC_WAITPIN_IDX1,
> + GPMC_WAITPIN_IDX2,
> + GPMC_WAITPIN_IDX3,
> + GPMC_NR_WAITPIN
> +};
Max number of wait pins is 3 for omap4/5. I know that we discussed this
in the past, but are you not supporting these devices are the moment? I
know that you have not done the hwmod for these, but still I was hoping
that you would take these into account.
> +
> +enum {
> + LOW,
> + HIGH
> +};
To be honest, I don't see the point in either of the above enums when
you have the definitions at the bottom. Seems that one set of
definitions should be enough.
> struct gpmc_client_irq {
> unsigned irq;
> u32 bitmask;
> @@ -140,6 +155,8 @@ struct gpmc_peripheral {
> struct platform_device *pdev;
> };
>
> +static unsigned gpmc_waitpin_map;
> +
> static struct gpmc_client_irq gpmc_client_irq[GPMC_NR_IRQ];
> static struct irq_chip gpmc_irq_chip;
> static unsigned gpmc_irq_start;
> @@ -1162,6 +1179,62 @@ static void gpmc_print_cs_timings(int cs)
> gpmc_get_one_timing(cs, GPMC_CS_CONFIG6, 7, 7));
> }
>
> +static int gpmc_setup_cs_waitpin(struct gpmc_peripheral *g_per, unsigned cs,
> + unsigned conf)
> +{
> + unsigned idx;
> + bool polarity = 0;
> + u32 l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
> +
> + switch (conf & GPMC_WAITPIN_MASK) {
> + case GPMC_WAITPIN_0:
> + idx = GPMC_WAITPIN_IDX0;
For example, here you could have ...
idx = GPMC_WAITPIN_0 - 1;
> + break;
> + case GPMC_WAITPIN_1:
> + idx = GPMC_WAITPIN_IDX1;
> + break;
> + case GPMC_WAITPIN_2:
> + idx = GPMC_WAITPIN_IDX2;
> + break;
> + case GPMC_WAITPIN_3:
> + idx = GPMC_WAITPIN_IDX3;
> + break;
> + /* no waitpin */
> + case 0:
> + return 0;
> + break;
> + default:
> + dev_err(gpmc_dev, "multiple waitpins selected on CS:%u\n", cs);
> + return -EINVAL;
> + break;
> + }
> +
> + polarity = !!(conf & GPMC_WAITPIN_ACTIVE_HIGH);
> +
> + if (g_per->have_waitpin) {
> + if (g_per->waitpin != idx ||
> + g_per->waitpin_polarity != polarity) {
> + dev_err(gpmc_dev, "error: conflict: waitpin %u with polarity %d on device %s.%d\n",
> + g_per->waitpin, g_per->waitpin_polarity,
> + g_per->name, g_per->id);
> + return -EBUSY;
> + }
> + } else {
> + g_per->have_waitpin = true;
> + g_per->waitpin = idx;
> + g_per->waitpin_polarity = polarity;
> + }
> +
> + l |= conf & GPMC_CONFIG1_WAIT_WRITE_MON;
> + l |= conf & GPMC_CONFIG1_WAIT_READ_MON;
> + l &= ~GPMC_CONFIG1_WAIT_PIN_SEL_MASK;
> + l |= GPMC_CONFIG1_WAIT_PIN_SEL(idx);
> +
> + gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, l);
> +
> + return 0;
> +}
> +
> static inline unsigned gpmc_bit_to_irq(unsigned bitmask)
> {
> return bitmask;
> @@ -1185,6 +1258,55 @@ static __devinit int gpmc_setup_cs_irq(struct gpmc_cs_data *cs,
> return n;
> }
>
> +static inline int gpmc_waitpin_is_reserved(unsigned waitpin)
> +{
> + return gpmc_waitpin_map & (0x1 << waitpin);
> +}
> +
> +static inline void gpmc_reserve_waitpin(unsigned waitpin)
> +{
> + gpmc_waitpin_map &= ~(0x1 << waitpin);
> + gpmc_waitpin_map |= (0x1 << waitpin);
> +}
> +
> +static int gpmc_waitpin_request(unsigned waitpin)
> +{
> + if (!(waitpin < GPMC_NR_WAITPIN))
> + return -ENODEV;
> +
> + if (gpmc_waitpin_is_reserved(waitpin))
> + return -EBUSY;
> + else
> + gpmc_reserve_waitpin(waitpin);
> +
> + return 0;
> +}
> +
> +static int gpmc_setup_waitpin(struct gpmc_peripheral *g_per)
> +{
> + int ret;
> + u32 l, shift;
> +
> + if (!g_per->have_waitpin)
> + return 0;
> +
> + ret = gpmc_waitpin_request(g_per->waitpin);
> + if (IS_ERR_VALUE(ret)) {
> + dev_err(gpmc_dev, "waitpin %u reserved\n", g_per->waitpin);
> + return ret;
> + }
> +
> + l = gpmc_read_reg(GPMC_CONFIG);
> + shift = g_per->waitpin + GPMC_CONFIG_WAITPIN_POLARITY_SHIFT;
> + if (g_per->waitpin_polarity == HIGH)
> + l |= 1 << shift;
> + else
> + l &= ~(1 << shift);
> + gpmc_write_reg(GPMC_CONFIG, l);
Looks like another good place for a _gpmc_cs_set_bit() function.
Jon
> +
> + return 0;
> +}
> +
> static __devinit int gpmc_probe(struct platform_device *pdev)
> {
> u32 l;
> diff --git a/arch/arm/plat-omap/include/plat/gpmc.h b/arch/arm/plat-omap/include/plat/gpmc.h
> index ff3f32c..e1b130c 100644
> --- a/arch/arm/plat-omap/include/plat/gpmc.h
> +++ b/arch/arm/plat-omap/include/plat/gpmc.h
> @@ -64,6 +64,7 @@
> #define GPMC_CONFIG1_WAIT_WRITE_MON (1 << 21)
> #define GPMC_CONFIG1_WAIT_MON_IIME(val) ((val & 3) << 18)
> #define GPMC_CONFIG1_WAIT_PIN_SEL(val) ((val & 3) << 16)
> +#define GPMC_CONFIG1_WAIT_PIN_SEL_MASK GPMC_CONFIG1_WAIT_PIN_SEL(3)
> #define GPMC_CONFIG1_DEVICESIZE(val) ((val & 3) << 12)
> #define GPMC_CONFIG1_DEVICESIZE_8 GPMC_CONFIG1_DEVICESIZE(0)
> #define GPMC_CONFIG1_DEVICESIZE_16 GPMC_CONFIG1_DEVICESIZE(1)
> @@ -78,6 +79,14 @@
> #define GPMC_CONFIG1_FCLK_DIV4 (GPMC_CONFIG1_FCLK_DIV(3))
> #define GPMC_CONFIG7_CSVALID (1 << 6)
>
> +#define GPMC_WAITPIN_ACTIVE_HIGH (1 << 4)
> +#define GPMC_WAITPIN_ACTIVE_LOW (0 << 4)
> +#define GPMC_WAITPIN_0 (1 << 0)
> +#define GPMC_WAITPIN_1 (1 << 1)
> +#define GPMC_WAITPIN_2 (1 << 2)
> +#define GPMC_WAITPIN_3 (1 << 3)
> +#define GPMC_WAITPIN_MASK (GPMC_WAITPIN_0 | GPMC_WAITPIN_1 | \
> + GPMC_WAITPIN_2 | GPMC_WAITPIN_3)
> #define GPMC_DEVICETYPE_NOR 0
> #define GPMC_DEVICETYPE_NAND 2
> #define GPMC_CONFIG_WRITEPROTECT 0x00000010
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