[Intel-gfx] [PATCH 1/3] drm/i915: introduce REG_BIT() and REG_FIELD_MASK() to define register contents
Rodrigo Vivi
rodrigo.vivi at intel.com
Wed Oct 3 16:54:24 UTC 2018
On Wed, Oct 03, 2018 at 07:05:21PM +0300, Jani Nikula wrote:
> Introduce REG_BIT(n) to define register bits and REG_FIELD_MASK(h, l) to
> define register field masks.
>
> We define the above as wrappers to BIT() and GENMASK() respectively to
> force u32 type to go with our register size. Additionally, the specified
> type will be helpful with follow-up to define and use register field
> values through bitfield operations, and the macro wrapper naming is
> aligned as well.
>
> The intention is that these are easier to get right and review against
> the spec than hand rolled masks.
My first impression was that reg rage as mask would get harder to code and
review, but it is just because I'm used to the current style....
But when thinking the real case of looking to the spec and writing the code
and/or reviewing it, the range makes indeed clear.
>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
> ---
> drivers/gpu/drm/i915/i915_reg.h | 68 +++++++++++++++++++++++------------------
> drivers/gpu/drm/i915/intel_dp.c | 2 +-
> 2 files changed, 40 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index a71c507cfb9b..ac9258769435 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -25,6 +25,8 @@
> #ifndef _I915_REG_H_
> #define _I915_REG_H_
>
> +#include <linux/bits.h>
> +
> /**
> * DOC: The i915 register macro definition style guide
> *
> @@ -59,15 +61,13 @@
> * significant to least significant bit. Indent the register content macros
> * using two extra spaces between ``#define`` and the macro name.
> *
> - * For bit fields, define a ``_MASK`` and a ``_SHIFT`` macro. Define bit field
> - * contents so that they are already shifted in place, and can be directly
> - * OR'd. For convenience, function-like macros may be used to define bit fields,
> - * but do note that the macros may be needed to read as well as write the
> - * register contents.
> + * For bit fields, define a ``_MASK`` and a ``_SHIFT`` macro. Use
> + * ``REG_FIELD_MASK()`` to define _MASK. Define bit field contents so that they
> + * are already shifted in place, and can be directly OR'd. For convenience,
> + * function-like macros may be used to define bit fields, but do note that the
> + * macros may be needed to read as well as write the register contents.
can we add a note that this is all inclusive bits on the range?
> *
> - * Define bits using ``(1 << N)`` instead of ``BIT(N)``. We may change this in
> - * the future, but this is the prevailing style. Do **not** add ``_BIT`` suffix
> - * to the name.
> + * Define bits using ``REG_BIT(N)``. Do **not** add ``_BIT`` suffix to the name.
> *
> * Group the register and its contents together without blank lines, separate
> * from other registers and their contents with one blank line.
> @@ -105,8 +105,8 @@
> * #define _FOO_A 0xf000
> * #define _FOO_B 0xf001
> * #define FOO(pipe) _MMIO_PIPE(pipe, _FOO_A, _FOO_B)
> - * #define FOO_ENABLE (1 << 31)
> - * #define FOO_MODE_MASK (0xf << 16)
> + * #define FOO_ENABLE REG_BIT(31)
> + * #define FOO_MODE_MASK REG_FIELD_MASK(19, 16)
> * #define FOO_MODE_SHIFT 16
> * #define FOO_MODE_BAR (0 << 16)
> * #define FOO_MODE_BAZ (1 << 16)
> @@ -116,6 +116,17 @@
> * #define GEN8_BAR _MMIO(0xb888)
> */
>
> +/*
> + * Macro for defining register bits. Local wrapper for BIT() to force u32.
> + */
> +#define REG_BIT(n) ((u32)BIT(n))
> +
> +/*
> + * Macro for defining register field masks. Local wrapper for GENMASK() to force
> + * u32.
> + */
> +#define REG_FIELD_MASK(h, l) ((u32)GENMASK(h, l))
> +
> typedef struct {
> uint32_t reg;
> } i915_reg_t;
> @@ -4612,7 +4623,7 @@ enum {
>
> #define _PP_STATUS 0x61200
> #define PP_STATUS(pps_idx) _MMIO_PPS(pps_idx, _PP_STATUS)
> -#define PP_ON (1 << 31)
> +#define PP_ON REG_BIT(31)
> /*
> * Indicates that all dependencies of the panel are on:
> *
> @@ -4620,14 +4631,14 @@ enum {
> * - pipe enabled
> * - LVDS/DVOB/DVOC on
> */
> -#define PP_READY (1 << 30)
> +#define PP_READY REG_BIT(30)
> +#define PP_SEQUENCE_MASK REG_FIELD_MASK(29, 28)
> #define PP_SEQUENCE_NONE (0 << 28)
> #define PP_SEQUENCE_POWER_UP (1 << 28)
> #define PP_SEQUENCE_POWER_DOWN (2 << 28)
> -#define PP_SEQUENCE_MASK (3 << 28)
> #define PP_SEQUENCE_SHIFT 28
> -#define PP_CYCLE_DELAY_ACTIVE (1 << 27)
> -#define PP_SEQUENCE_STATE_MASK 0x0000000f
> +#define PP_CYCLE_DELAY_ACTIVE REG_BIT(27)
> +#define PP_SEQUENCE_STATE_MASK REG_FIELD_MASK(3, 0)
> #define PP_SEQUENCE_STATE_OFF_IDLE (0x0 << 0)
> #define PP_SEQUENCE_STATE_OFF_S0_1 (0x1 << 0)
> #define PP_SEQUENCE_STATE_OFF_S0_2 (0x2 << 0)
> @@ -4640,42 +4651,41 @@ enum {
>
> #define _PP_CONTROL 0x61204
> #define PP_CONTROL(pps_idx) _MMIO_PPS(pps_idx, _PP_CONTROL)
> +#define PANEL_UNLOCK_MASK REG_FIELD_MASK(31, 16)
> #define PANEL_UNLOCK_REGS (0xabcd << 16)
> -#define PANEL_UNLOCK_MASK (0xffff << 16)
> -#define BXT_POWER_CYCLE_DELAY_MASK 0x1f0
> +#define BXT_POWER_CYCLE_DELAY_MASK REG_FIELD_MASK(8, 4)
> #define BXT_POWER_CYCLE_DELAY_SHIFT 4
> -#define EDP_FORCE_VDD (1 << 3)
> -#define EDP_BLC_ENABLE (1 << 2)
> -#define PANEL_POWER_RESET (1 << 1)
> -#define PANEL_POWER_OFF (0 << 0)
> -#define PANEL_POWER_ON (1 << 0)
> +#define EDP_FORCE_VDD REG_BIT(3)
> +#define EDP_BLC_ENABLE REG_BIT(2)
> +#define PANEL_POWER_RESET REG_BIT(1)
> +#define PANEL_POWER_ON REG_BIT(0)
>
> #define _PP_ON_DELAYS 0x61208
> #define PP_ON_DELAYS(pps_idx) _MMIO_PPS(pps_idx, _PP_ON_DELAYS)
> #define PANEL_PORT_SELECT_SHIFT 30
> -#define PANEL_PORT_SELECT_MASK (3 << 30)
> +#define PANEL_PORT_SELECT_MASK REG_FIELD_MASK(31, 30)
> #define PANEL_PORT_SELECT_LVDS (0 << 30)
> #define PANEL_PORT_SELECT_DPA (1 << 30)
> #define PANEL_PORT_SELECT_DPC (2 << 30)
> #define PANEL_PORT_SELECT_DPD (3 << 30)
> #define PANEL_PORT_SELECT_VLV(port) ((port) << 30)
> -#define PANEL_POWER_UP_DELAY_MASK 0x1fff0000
> +#define PANEL_POWER_UP_DELAY_MASK REG_FIELD_MASK(28, 16)
> #define PANEL_POWER_UP_DELAY_SHIFT 16
> -#define PANEL_LIGHT_ON_DELAY_MASK 0x1fff
> +#define PANEL_LIGHT_ON_DELAY_MASK REG_FIELD_MASK(12, 0)
> #define PANEL_LIGHT_ON_DELAY_SHIFT 0
>
> #define _PP_OFF_DELAYS 0x6120C
> #define PP_OFF_DELAYS(pps_idx) _MMIO_PPS(pps_idx, _PP_OFF_DELAYS)
> -#define PANEL_POWER_DOWN_DELAY_MASK 0x1fff0000
> +#define PANEL_POWER_DOWN_DELAY_MASK REG_FIELD_MASK(28, 16)
> #define PANEL_POWER_DOWN_DELAY_SHIFT 16
> -#define PANEL_LIGHT_OFF_DELAY_MASK 0x1fff
> +#define PANEL_LIGHT_OFF_DELAY_MASK REG_FIELD_MASK(12, 0)
> #define PANEL_LIGHT_OFF_DELAY_SHIFT 0
>
> #define _PP_DIVISOR 0x61210
> #define PP_DIVISOR(pps_idx) _MMIO_PPS(pps_idx, _PP_DIVISOR)
> -#define PP_REFERENCE_DIVIDER_MASK 0xffffff00
> +#define PP_REFERENCE_DIVIDER_MASK REG_FIELD_MASK(31, 8)
> #define PP_REFERENCE_DIVIDER_SHIFT 8
> -#define PANEL_POWER_CYCLE_DELAY_MASK 0x1f
> +#define PANEL_POWER_CYCLE_DELAY_MASK REG_FIELD_MASK(4, 0)
> #define PANEL_POWER_CYCLE_DELAY_SHIFT 0
>
> /* Panel fitting */
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 15a981ef5966..31eef9b0e33b 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -1040,7 +1040,7 @@ static int edp_notify_handler(struct notifier_block *this, unsigned long code,
>
> /* 0x1F write to PP_DIV_REG sets max cycle delay */
> I915_WRITE(pp_div_reg, pp_div | 0x1F);
> - I915_WRITE(pp_ctrl_reg, PANEL_UNLOCK_REGS | PANEL_POWER_OFF);
> + I915_WRITE(pp_ctrl_reg, PANEL_UNLOCK_REGS);
> msleep(intel_dp->panel_power_cycle_delay);
> }
>
> --
> 2.11.0
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
More information about the Intel-gfx
mailing list