Re: [PATCH v3 (alternative) 1/3] drm/exynos: fimd: ensure proper hw state in fimd_clear_channel()

[Inki Dae <inki.dae@samsung.com>]

On 2015년 06월 12일 18:07, Marek Szyprowski wrote:
> One should not do any assumptions on the stare of the fimd hardware
> during driver initialization, so to properly reset fimd before enabling
> IOMMU, one should ensure that all power domains and clocks are really
> enabled. This patch adds pm_runtime and clocks management in the
> fimd_clear_channel() function to ensure that any access to fimd
> registers will be performed with clocks and power domains enabled.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
> ---
> Changelog:
> v3 (alternative):
> - araranged code by moving fimd_{enable,disable}_vblank functions before
>   fimd_clear_channel to avoid forward declaration usage

Marek,

For the iommu and atomic feature test, I merged below patches in
addition and tested them.

[PATCH v2 1/3] drm/exynos: remove to call mixer_wait_for_vblank
[PATCH v2 2/3] drm/exynos: remove chained calls to enable
[PATCH v2 3/3] drm/exynos: initialize VIDCON0 when fimd is disabled


However, I see below one warning log,

[    1.227115] [drm] Initialized drm 1.1.0 20060810
[    1.235852] exynos-drm exynos-drm: bound exynos-drm-vidi (ops
vidi_component_ops)
[    1.253548] ------------[ cut here ]------------
[    1.256700] WARNING: CPU: 0 PID: 0 at drivers/gpu/drm/drm_irq.c:1718
drm_handle_vblank+0x2a0/0x308()
[    1.265800] Modules linked in:
[    1.268844] CPU: 0 PID: 0 Comm: swapper/0 Not tainted
4.1.0-rc4-00574-gf8eb363-dirty #1412
[    1.277085] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[    1.283184] [<c0015464>] (unwind_backtrace) from [<c00123c0>]
(show_stack+0x10/0x14)
[    1.288540] exynos-drm exynos-drm: bound 11c00000.fimd (ops
fimd_component_ops)
[    1.288883] exynos-drm exynos-drm: bound 11c80000.dsi (ops
exynos_dsi_component_ops)
[    1.288888] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[    1.288891] [drm] No driver support for vblank timestamp query.
[    1.288932] [drm] Initialized exynos 1.0.0 20110530 on minor 0
[    1.324248] [<c00123c0>] (show_stack) from [<c0528f74>]
(dump_stack+0x84/0xc4)
[    1.331437] [<c0528f74>] (dump_stack) from [<c00246ac>]
(warn_slowpath_common+0x80/0xb0)
[    1.339504] [<c00246ac>] (warn_slowpath_common) from [<c0024778>]
(warn_slowpath_null+0x1c/0x24)
[    1.348270] [<c0024778>] (warn_slowpath_null) from [<c029c898>]
(drm_handle_vblank+0x2a0/0x308)
[    1.356965] [<c029c898>] (drm_handle_vblank) from [<c02b8c80>]
(fimd_irq_handler+0x78/0xd0)
[    1.365292] [<c02b8c80>] (fimd_irq_handler) from [<c00608f8>]
(handle_irq_event_percpu+0x78/0x134)
[    1.374231] [<c00608f8>] (handle_irq_event_percpu) from [<c00609f0>]
(handle_irq_event+0x3c/0x5c)
[    1.374244] [<c00609f0>] (handle_irq_event) from [<c0063698>]
(handle_level_irq+0xc4/0x13c)
[    1.374256] [<c0063698>] (handle_level_irq) from [<c005ff7c>]
(generic_handle_irq+0x2c/0x3c)
[    1.374269] [<c005ff7c>] (generic_handle_irq) from [<c02214ec>]
(combiner_handle_cascade_irq+0x94/0x100)
[    1.374281] [<c02214ec>] (combiner_handle_cascade_irq) from
[<c005ff7c>] (generic_handle_irq+0x2c/0x3c)
[    1.374290] [<c005ff7c>] (generic_handle_irq) from [<c0060248>]
(__handle_domain_irq+0x7c/0xec)
[    1.374300] [<c0060248>] (__handle_domain_irq) from [<c0009434>]
(gic_handle_irq+0x30/0x68)


And below one page fault error when modetest is terminated,

# modetest -M exynos -v -s 31@29:720x1280
setting mode 720x1280-60Hz@XR24 on connectors 31, crtc 29
freq: 59.99Hz

[   34.831025] PAGE FAULT occurred at 0x20400000 by 11e20000.sysmmu(Page
table base: 0x6e324000)
[   34.838072]  Lv1 entry: 0x6e92dc01
[   34.841489] ------------[ cut here ]------------
[   34.846058] kernel BUG at drivers/iommu/exynos-iommu.c:364!
[   34.851614] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
[   34.857428] Modules linked in:
[   34.860472] CPU: 0 PID: 6 Comm: kworker/u8:0 Tainted: G        W
  4.1.0-rc4-00574-gf8eb363-dirty #1412
[   34.870188] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[   34.876273] Workqueue: events_unbound async_run_entry_fn
[   34.881560] task: ee879540 ti: ee8a2000 task.ti: ee8a2000
[   34.886946] PC is at exynos_sysmmu_irq+0x184/0x208
[   34.891716] LR is at exynos_sysmmu_irq+0xd4/0x208
[   34.896404] pc : [<c02880d0>]    lr : [<c0288020>]    psr: 60000193
[   34.896404] sp : ee8a3c00  ip : 00000000  fp : eeacbc10
[   34.907860] r10: c07c27ef  r9 : 00000204  r8 : 20400000
[   34.913068] r7 : ee324000  r6 : ee9b3428  r5 : ee9b3410  r4 : 00000000
[   34.919577] r3 : 6e92dc01  r2 : 6e92dc01  r1 : eea55810  r0 : eeb0a000
[   34.926089] Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM
Segment kernel
[   34.933466] Control: 10c5387d  Table: 6dd2c04a  DAC: 00000015
[   34.939195] Process kworker/u8:0 (pid: 6, stack limit = 0xee8a2210)
[   34.945444] Stack: (0xee8a3c00 to 0xee8a4000)
[   34.949788] 3c00: ee8a3c0c c0049df8 00000000 6e324000 0003d4f3
ee9b13c0 ee84ad20 00000000
[   34.957947] 3c20: 00000000 00000026 ee84acc0 c00608f8 60000093
eef84580 ee84acc0 ee84ad20
[   34.966106] 3c40: ee9b13c0 00000015 ee804450 ee8a3cd8 ee808000
c00609f0 ee84acc0 ee84ad20
[   34.974265] 3c60: ee807000 c0063698 00000026 c079d6f8 ee807000
c005ff7c 0000000a c02214ec
[   34.982424] 3c80: 00000015 00000000 00000015 00000000 00000001
c005ff7c c0789aac c0060248
[   34.990583] 3ca0: f002000c 00000015 c078e7ac ee8a3cd8 f0020000
ee8a2000 00000001 c0009434
[   34.998742] 3cc0: c052e8fc 60000013 ffffffff ee8a3d0c 00000004
c0012ec0 eeacbd18 ee879540
[   35.006901] 3ce0: 00000000 00000271 eeacbd18 00000000 eea55010
c078e100 00000004 ee8a2000
[   35.015061] 3d00: 00000001 eeacbc10 eeacbd88 ee8a3d20 c052e8f8
c052e8fc 60000013 ffffffff
[   35.023220] 3d20: eeacbd18 c02dab48 20000113 00000003 60000013
eeacbd18 00000004 eeacbc60
[   35.031379] 3d40: ffff30d5 eeacbca8 eeacbd18 00000004 60000013
ffff30d5 c0802fe8 c02db05c
[   35.039538] 3d60: eeacbc60 00000002 c078e100 eeacbc60 ffff30d5
c03b0f2c c078bb40 ee8a3e28
[   35.047697] 3d80: 00000001 ee8a3db8 eeacbc70 00000002 eeacbc70
ee8a3db8 eeacbca8 c052e880
[   35.055857] 3da0: eeacbc70 c052d818 00000000 00000009 00000000
c002791c ee8a3db8 11111111
[   35.064016] 3dc0: 11111111 ee8a3dc4 11111111 eeacbc60 00000002
c078e100 ee8a3e28 ffff30d5
[   35.072175] 3de0: c0802fe8 00000001 ee80b400 c03ac4cc 00000000
eeacbc60 ee8a3e28 00000002
[   35.080334] 3e00: eea47ac0 00000000 ee849d00 c03ac69c 00000000
00000001 00000001 eea47ac0
[   35.088493] 3e20: eea47ac0 c02e9f10 00000009 60000001 eea47ac0
00010009 00000001 eea47ac0
[   35.096653] 3e40: ee29149c 00000000 ee00c200 c02e5bdc 00000001
c004425c ee00c200 00000047
[   35.104812] 3e60: ee00c200 ee00c200 ee8a3eb4 ee8a3eb4 00000000
c02e5c5c ee00c200 ee00c200
[   35.112971] 3e80: 00000047 c02e564c ee00c200 00000047 ee8a3eb4
ee80da00 00000000 c02e5704
[   35.121130] 3ea0: eeafd800 c07c5020 eeafd84c c025383c ee849d00
c052d110 eeafd800 c0252a48
[   35.129289] 3ec0: ee914724 c07c5020 edcc9c40 c0252f58 edcc9c50
c003ed48 eef84580 eea2f700
[   35.137448] 3ee0: ee849d00 edcc9c50 ee80b400 c0037944 ee8a2000
ee80b400 00000001 ee80b400
[   35.145608] 3f00: ee849d18 ee80b420 ee8a2000 00000088 c07c27bc
ee849d00 ee80b400 c0037ba0
[   35.153767] 3f20: c078e100 ee80b570 ee849d00 00000000 ee84b540
ee849d00 c0037b54 00000000
[   35.161926] 3f40: 00000000 00000000 00000000 c003c8b8 ffffffff
00000000 ffffffff ee849d00
[   35.170085] 3f60: 00000000 00000000 dead4ead ffffffff ffffffff
ee8a3f74 ee8a3f74 00000000
[   35.178245] 3f80: 00000000 dead4ead ffffffff ffffffff ee8a3f90
ee8a3f90 ee8a3fac ee84b540
[   35.186403] 3fa0: c003c7dc 00000000 00000000 c000f5a0 00000000
00000000 00000000 00000000
[   35.194562] 3fc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[   35.202722] 3fe0: 00000000 00000000 00000000 00000000 00000013
00000000 ffffffff ffffffff
[   35.210894] [<c02880d0>] (exynos_sysmmu_irq) from [<c00608f8>]
(handle_irq_event_percpu+0x78/0x134)
[   35.219914] [<c00608f8>] (handle_irq_event_percpu) from [<c00609f0>]
(handle_irq_event+0x3c/0x5c)
[   35.228768] [<c00609f0>] (handle_irq_event) from [<c0063698>]
(handle_level_irq+0xc4/0x13c)
[   35.237101] [<c0063698>] (handle_level_irq) from [<c005ff7c>]
(generic_handle_irq+0x2c/0x3c)
[   35.245521] [<c005ff7c>] (generic_handle_irq) from [<c02214ec>]
(combiner_handle_cascade_irq+0x94/0x100)
[   35.254980] [<c02214ec>] (combiner_handle_cascade_irq) from
[<c005ff7c>] (generic_handle_irq+0x2c/0x3c)
[   35.264353] [<c005ff7c>] (generic_handle_irq) from [<c0060248>]
(__handle_domain_irq+0x7c/0xec)
[   35.273034] [<c0060248>] (__handle_domain_irq) from [<c0009434>]
(gic_handle_irq+0x30/0x68)
[   35.281366] [<c0009434>] (gic_handle_irq) from [<c0012ec0>]
(__irq_svc+0x40/0x74)

Could you check the iommu with atomic feature? I tested these features
on trats2 board, and enabled one more crtc drivers - HDMI, VIDI, and FIMD.

To other Exynos guys,
could you guys check the same issues also? If you give some helps to us,
we'd be glad.

Thanks,
Inki Dae

> 
> v2:
> - rebased onto latest exynos-drm-next branch with atomic mode setting
>   patches applied.
> 
> 
>  drivers/gpu/drm/exynos/exynos_drm_fimd.c | 130 +++++++++++++++++--------------
>  1 file changed, 71 insertions(+), 59 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> index 96618534358e..f490895a8b02 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> @@ -196,6 +196,62 @@ static inline struct fimd_driver_data *drm_fimd_get_driver_data(
>  	return (struct fimd_driver_data *)of_id->data;
>  }
>  
> +static int fimd_enable_vblank(struct exynos_drm_crtc *crtc)
> +{
> +	struct fimd_context *ctx = crtc->ctx;
> +	u32 val;
> +
> +	if (ctx->suspended)
> +		return -EPERM;
> +
> +	if (!test_and_set_bit(0, &ctx->irq_flags)) {
> +		val = readl(ctx->regs + VIDINTCON0);
> +
> +		val |= VIDINTCON0_INT_ENABLE;
> +
> +		if (ctx->i80_if) {
> +			val |= VIDINTCON0_INT_I80IFDONE;
> +			val |= VIDINTCON0_INT_SYSMAINCON;
> +			val &= ~VIDINTCON0_INT_SYSSUBCON;
> +		} else {
> +			val |= VIDINTCON0_INT_FRAME;
> +
> +			val &= ~VIDINTCON0_FRAMESEL0_MASK;
> +			val |= VIDINTCON0_FRAMESEL0_VSYNC;
> +			val &= ~VIDINTCON0_FRAMESEL1_MASK;
> +			val |= VIDINTCON0_FRAMESEL1_NONE;
> +		}
> +
> +		writel(val, ctx->regs + VIDINTCON0);
> +	}
> +
> +	return 0;
> +}
> +
> +static void fimd_disable_vblank(struct exynos_drm_crtc *crtc)
> +{
> +	struct fimd_context *ctx = crtc->ctx;
> +	u32 val;
> +
> +	if (ctx->suspended)
> +		return;
> +
> +	if (test_and_clear_bit(0, &ctx->irq_flags)) {
> +		val = readl(ctx->regs + VIDINTCON0);
> +
> +		val &= ~VIDINTCON0_INT_ENABLE;
> +
> +		if (ctx->i80_if) {
> +			val &= ~VIDINTCON0_INT_I80IFDONE;
> +			val &= ~VIDINTCON0_INT_SYSMAINCON;
> +			val &= ~VIDINTCON0_INT_SYSSUBCON;
> +		} else
> +			val &= ~VIDINTCON0_INT_FRAME;
> +
> +		writel(val, ctx->regs + VIDINTCON0);
> +	}
> +}
> +
>  static void fimd_wait_for_vblank(struct exynos_drm_crtc *crtc)
>  {
>  	struct fimd_context *ctx = crtc->ctx;
> @@ -248,6 +304,12 @@ static void fimd_clear_channel(struct fimd_context *ctx)
>  
>  	DRM_DEBUG_KMS("%s\n", __FILE__);
>  
> +	/* Hardware is in unknown state, so ensure it gets enabled properly */
> +	pm_runtime_get_sync(ctx->dev);
> +
> +	clk_prepare_enable(ctx->bus_clk);
> +	clk_prepare_enable(ctx->lcd_clk);
> +
>  	/* Check if any channel is enabled. */
>  	for (win = 0; win < WINDOWS_NR; win++) {
>  		u32 val = readl(ctx->regs + WINCON(win));
> @@ -265,12 +327,17 @@ static void fimd_clear_channel(struct fimd_context *ctx)
>  
>  	/* Wait for vsync, as disable channel takes effect at next vsync */
>  	if (ch_enabled) {
> -		unsigned int state = ctx->suspended;
> -
> -		ctx->suspended = 0;
> +		ctx->suspended = false;
> +		fimd_enable_vblank(ctx->crtc);
>  		fimd_wait_for_vblank(ctx->crtc);
> -		ctx->suspended = state;
> +		fimd_disable_vblank(ctx->crtc);
> +		ctx->suspended = true;
>  	}
> +
> +	clk_disable_unprepare(ctx->lcd_clk);
> +	clk_disable_unprepare(ctx->bus_clk);
> +
> +	pm_runtime_put(ctx->dev);
>  }
>  
>  static int fimd_iommu_attach_devices(struct fimd_context *ctx,
> @@ -434,61 +501,6 @@ static void fimd_commit(struct exynos_drm_crtc *crtc)
>  	writel(val, ctx->regs + VIDCON0);
>  }
>  
> -static int fimd_enable_vblank(struct exynos_drm_crtc *crtc)
> -{
> -	struct fimd_context *ctx = crtc->ctx;
> -	u32 val;
> -
> -	if (ctx->suspended)
> -		return -EPERM;
> -
> -	if (!test_and_set_bit(0, &ctx->irq_flags)) {
> -		val = readl(ctx->regs + VIDINTCON0);
> -
> -		val |= VIDINTCON0_INT_ENABLE;
> -
> -		if (ctx->i80_if) {
> -			val |= VIDINTCON0_INT_I80IFDONE;
> -			val |= VIDINTCON0_INT_SYSMAINCON;
> -			val &= ~VIDINTCON0_INT_SYSSUBCON;
> -		} else {
> -			val |= VIDINTCON0_INT_FRAME;
> -
> -			val &= ~VIDINTCON0_FRAMESEL0_MASK;
> -			val |= VIDINTCON0_FRAMESEL0_VSYNC;
> -			val &= ~VIDINTCON0_FRAMESEL1_MASK;
> -			val |= VIDINTCON0_FRAMESEL1_NONE;
> -		}
> -
> -		writel(val, ctx->regs + VIDINTCON0);
> -	}
> -
> -	return 0;
> -}
> -
> -static void fimd_disable_vblank(struct exynos_drm_crtc *crtc)
> -{
> -	struct fimd_context *ctx = crtc->ctx;
> -	u32 val;
> -
> -	if (ctx->suspended)
> -		return;
> -
> -	if (test_and_clear_bit(0, &ctx->irq_flags)) {
> -		val = readl(ctx->regs + VIDINTCON0);
> -
> -		val &= ~VIDINTCON0_INT_ENABLE;
> -
> -		if (ctx->i80_if) {
> -			val &= ~VIDINTCON0_INT_I80IFDONE;
> -			val &= ~VIDINTCON0_INT_SYSMAINCON;
> -			val &= ~VIDINTCON0_INT_SYSSUBCON;
> -		} else
> -			val &= ~VIDINTCON0_INT_FRAME;
> -
> -		writel(val, ctx->regs + VIDINTCON0);
> -	}
> -}
>  
>  static void fimd_win_set_pixfmt(struct fimd_context *ctx, unsigned int win)
>  {
>