[PATCH v2] OMAP2PLUS: DSS: Ensure DSS works correctly if display is enabled in bootloader
Paul Walmsley
paul at pwsan.com
Mon Oct 3 15:30:06 EDT 2011
Hi Archit,
thanks for the quick and informative response -
On Mon, 3 Oct 2011, Archit Taneja wrote:
> On Monday 03 October 2011 10:15 AM, Paul Walmsley wrote:
> > On Mon, 12 Sep 2011, Archit Taneja wrote:
> >
> > > diff --git a/arch/arm/mach-omap2/display.c b/arch/arm/mach-omap2/display.c
> > > index 93db7c1..eab81f4 100644
> > > --- a/arch/arm/mach-omap2/display.c
> > > +++ b/arch/arm/mach-omap2/display.c
> > > @@ -30,6 +30,30 @@
> > >
> > > #include "control.h"
> > >
> > > +#define DISPC_BASE_OMAP2 0x48050400
> > > +#define DISPC_BASE_OMAP4 0x48041000
> >
> > These should definitely not be needed -- they can be obtained from the
> > hwmod data and there is clearly something wrong if any IP block addresses
> > exist outside of those data files.
>
> The reason we had to do this was because the function omap_dss_reset()
> is tied to the dss hwmod and not dispc hwmod. > Hence, we don't have
> DISPC related info through the hwmod struct available through
> omap_dss_reset().
You're right. My replacement patch is broken in that regard.
> Could you suggest how we could go about this? Is there a way to access dispc
> hwmod's data in dss hwmod's custom reset function?
There is. The dss hwmod's custom reset function can call
omap_hwmod_lookup() for the dss_dispc hwmod. It's not the best long term
solution, but should work until we can determine the best way to handle
these types of subsystem resets with hwmod and/or DT. Revised patch
below.
> I agree with all the other comments and things you have done in the patch you
> made. Thanks for the thorough review and the patch, i'll keep these comments
> in mind for future.
Thanks for looking over the revised patch and correcting my mistake,
- Paul
From: Archit Taneja <archit at ti.com>
Date: Mon, 12 Sep 2011 12:38:26 +0530
Subject: [PATCH] ARM: OMAP2PLUS: DSS: Ensure DSS works correctly if display
is enabled in bootloader
Resetting DISPC when a DISPC output is enabled causes the DSS to go into an
inconsistent state. Thus if the bootloader has enabled a display, the hwmod code
cannot reset the DISPC module just like that, but the outputs need to be
disabled first.
Add function dispc_disable_outputs() which disables all active overlay manager
and ensure all frame transfers are completed.
Modify omap_dss_reset() to call this function and clear DSS_CONTROL,
DSS_SDI_CONTROL and DSS_PLL_CONTROL so that DSS is in a clean state when the
DSS2 driver starts.
This resolves the hang issue(caused by a L3 error during boot) seen on the
beagle board C3, which has a factory bootloader that enables display. The issue
is resolved with this patch.
Acked-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
Tested-by: R, Sricharan <r.sricharan at ti.com>
Signed-off-by: Archit Taneja <archit at ti.com>
[paul at pwsan.com: restructured code, removed omap_{read,write}l(), removed
cpu_is_omap*() calls and converted to dev_attr]
Signed-off-by: Paul Walmsley <paul at pwsan.com>
---
arch/arm/mach-omap2/display.c | 125 ++++++++++++++++++++++++++
arch/arm/mach-omap2/display.h | 29 ++++++
arch/arm/mach-omap2/omap_hwmod_2420_data.c | 1 +
arch/arm/mach-omap2/omap_hwmod_2430_data.c | 1 +
arch/arm/mach-omap2/omap_hwmod_3xxx_data.c | 1 +
arch/arm/mach-omap2/omap_hwmod_44xx_data.c | 6 ++
arch/arm/mach-omap2/omap_hwmod_common_data.c | 4 +
arch/arm/mach-omap2/omap_hwmod_common_data.h | 4 +
8 files changed, 171 insertions(+), 0 deletions(-)
create mode 100644 arch/arm/mach-omap2/display.h
diff --git a/arch/arm/mach-omap2/display.c b/arch/arm/mach-omap2/display.c
index cdb675a..3bf8dbe 100644
--- a/arch/arm/mach-omap2/display.c
+++ b/arch/arm/mach-omap2/display.c
@@ -28,6 +28,33 @@
#include <plat/omap-pm.h>
#include <plat/common.h>
+#include "display.h"
+
+#define DISPC_CONTROL 0x0040
+#define DISPC_CONTROL2 0x0238
+#define DISPC_IRQSTATUS 0x0018
+
+#define DSS_SYSCONFIG 0x10
+#define DSS_SYSSTATUS 0x14
+#define DSS_CONTROL 0x40
+#define DSS_SDI_CONTROL 0x44
+#define DSS_PLL_CONTROL 0x48
+
+#define LCD_EN_MASK (0x1 << 0)
+#define DIGIT_EN_MASK (0x1 << 1)
+
+#define FRAMEDONE_IRQ_SHIFT 0
+#define EVSYNC_EVEN_IRQ_SHIFT 2
+#define EVSYNC_ODD_IRQ_SHIFT 3
+#define FRAMEDONE2_IRQ_SHIFT 22
+#define FRAMEDONETV_IRQ_SHIFT 24
+
+/*
+ * FRAMEDONE_IRQ_TIMEOUT: how long (in milliseconds) to wait during DISPC
+ * reset before deciding that something has gone wrong
+ */
+#define FRAMEDONE_IRQ_TIMEOUT 100
+
static struct platform_device omap_display_device = {
.name = "omapdss",
.id = -1,
@@ -128,6 +155,90 @@ int __init omap_display_init(struct omap_dss_board_info *board_data)
return r;
}
+static void dispc_disable_outputs(void)
+{
+ u32 v, irq_mask = 0;
+ bool lcd_en, digit_en, lcd2_en = false;
+ int i;
+ struct omap_dss_dispc_dev_attr *da;
+ struct omap_hwmod *oh;
+
+ oh = omap_hwmod_lookup("dss_dispc");
+ if (!oh) {
+ WARN(1, "display: could not disable outputs during reset - could not find dss_dispc hwmod\n");
+ return;
+ }
+
+ if (!oh->dev_attr) {
+ pr_err("display: could not disable outputs during reset due to missing dev_attr\n");
+ return;
+ }
+
+ da = (struct omap_dss_dispc_dev_attr *)oh->dev_attr;
+
+ /* store value of LCDENABLE and DIGITENABLE bits */
+ v = omap_hwmod_read(oh, DISPC_CONTROL);
+ lcd_en = v & LCD_EN_MASK;
+ digit_en = v & DIGIT_EN_MASK;
+
+ /* store value of LCDENABLE for LCD2 */
+ if (da->manager_count > 2) {
+ v = omap_hwmod_read(oh, DISPC_CONTROL2);
+ lcd2_en = v & LCD_EN_MASK;
+ }
+
+ if (!(lcd_en | digit_en | lcd2_en))
+ return; /* no managers currently enabled */
+
+ /*
+ * If any manager was enabled, we need to disable it before
+ * DSS clocks are disabled or DISPC module is reset
+ */
+ if (lcd_en)
+ irq_mask |= 1 << FRAMEDONE_IRQ_SHIFT;
+
+ if (digit_en) {
+ if (da->has_framedonetv_irq) {
+ irq_mask |= 1 << FRAMEDONETV_IRQ_SHIFT;
+ } else {
+ irq_mask |= 1 << EVSYNC_EVEN_IRQ_SHIFT |
+ 1 << EVSYNC_ODD_IRQ_SHIFT;
+ }
+ }
+
+ if (lcd2_en)
+ irq_mask |= 1 << FRAMEDONE2_IRQ_SHIFT;
+
+ /*
+ * clear any previous FRAMEDONE, FRAMEDONETV,
+ * EVSYNC_EVEN/ODD or FRAMEDONE2 interrupts
+ */
+ omap_hwmod_write(irq_mask, oh, DISPC_IRQSTATUS);
+
+ /* disable LCD and TV managers */
+ v = omap_hwmod_read(oh, DISPC_CONTROL);
+ v &= ~(LCD_EN_MASK | DIGIT_EN_MASK);
+ omap_hwmod_write(v, oh, DISPC_CONTROL);
+
+ /* disable LCD2 manager */
+ if (da->manager_count > 2) {
+ v = omap_hwmod_read(oh, DISPC_CONTROL2);
+ v &= ~LCD_EN_MASK;
+ omap_hwmod_write(v, oh, DISPC_CONTROL2);
+ }
+
+ i = 0;
+ while ((omap_hwmod_read(oh, DISPC_IRQSTATUS) & irq_mask) !=
+ irq_mask) {
+ i++;
+ if (i > FRAMEDONE_IRQ_TIMEOUT) {
+ pr_err("didn't get FRAMEDONE1/2 or TV interrupt\n");
+ break;
+ }
+ mdelay(1);
+ }
+}
+
#define MAX_MODULE_SOFTRESET_WAIT 10000
int omap_dss_reset(struct omap_hwmod *oh)
{
@@ -144,6 +255,20 @@ int omap_dss_reset(struct omap_hwmod *oh)
if (oc->_clk)
clk_enable(oc->_clk);
+ dispc_disable_outputs();
+
+ /* clear SDI registers */
+ if (cpu_is_omap3430()) {
+ omap_hwmod_write(0x0, oh, DSS_SDI_CONTROL);
+ omap_hwmod_write(0x0, oh, DSS_PLL_CONTROL);
+ }
+
+ /*
+ * clear DSS_CONTROL register to switch DSS clock sources to
+ * PRCM clock, if any
+ */
+ omap_hwmod_write(0x0, oh, DSS_CONTROL);
+
omap_test_timeout((omap_hwmod_read(oh, oh->class->sysc->syss_offs)
& SYSS_RESETDONE_MASK),
MAX_MODULE_SOFTRESET_WAIT, c);
diff --git a/arch/arm/mach-omap2/display.h b/arch/arm/mach-omap2/display.h
new file mode 100644
index 0000000..b871b01
--- /dev/null
+++ b/arch/arm/mach-omap2/display.h
@@ -0,0 +1,29 @@
+/*
+ * display.h - OMAP2+ integration-specific DSS header
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __ARCH_ARM_MACH_OMAP2_DISPLAY_H
+#define __ARCH_ARM_MACH_OMAP2_DISPLAY_H
+
+#include <linux/kernel.h>
+
+struct omap_dss_dispc_dev_attr {
+ u8 manager_count;
+ bool has_framedonetv_irq;
+};
+
+#endif
diff --git a/arch/arm/mach-omap2/omap_hwmod_2420_data.c b/arch/arm/mach-omap2/omap_hwmod_2420_data.c
index 6a9ef05..8cc0747 100644
--- a/arch/arm/mach-omap2/omap_hwmod_2420_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_2420_data.c
@@ -944,6 +944,7 @@ static struct omap_hwmod omap2420_dss_dispc_hwmod = {
.slaves_cnt = ARRAY_SIZE(omap2420_dss_dispc_slaves),
.omap_chip = OMAP_CHIP_INIT(CHIP_IS_OMAP2420),
.flags = HWMOD_NO_IDLEST,
+ .dev_attr = &omap2_3_dss_dispc_dev_attr
};
/* l4_core -> dss_rfbi */
diff --git a/arch/arm/mach-omap2/omap_hwmod_2430_data.c b/arch/arm/mach-omap2/omap_hwmod_2430_data.c
index 0515718..042a71f 100644
--- a/arch/arm/mach-omap2/omap_hwmod_2430_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_2430_data.c
@@ -1004,6 +1004,7 @@ static struct omap_hwmod omap2430_dss_dispc_hwmod = {
.slaves_cnt = ARRAY_SIZE(omap2430_dss_dispc_slaves),
.omap_chip = OMAP_CHIP_INIT(CHIP_IS_OMAP2430),
.flags = HWMOD_NO_IDLEST,
+ .dev_attr = &omap2_3_dss_dispc_dev_attr
};
/* l4_core -> dss_rfbi */
diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
index 6cb6731..3eee50e9 100644
--- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
@@ -1464,6 +1464,7 @@ static struct omap_hwmod omap3xxx_dss_dispc_hwmod = {
CHIP_GE_OMAP3430ES2 | CHIP_IS_OMAP3630ES1 |
CHIP_GE_OMAP3630ES1_1),
.flags = HWMOD_NO_IDLEST,
+ .dev_attr = &omap2_3_dss_dispc_dev_attr
};
/*
diff --git a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
index 7a7489e..17adfb3 100644
--- a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
@@ -1345,6 +1345,11 @@ static struct omap_hwmod_addr_space omap44xx_dss_dispc_addrs[] = {
{ }
};
+static struct omap_dss_dispc_dev_attr omap44xx_dss_dispc_dev_attr = {
+ .manager_count = 3,
+ .has_framedonetv_irq = 1
+};
+
/* l4_per -> dss_dispc */
static struct omap_hwmod_ocp_if omap44xx_l4_per__dss_dispc = {
.master = &omap44xx_l4_per_hwmod,
@@ -1376,6 +1381,7 @@ static struct omap_hwmod omap44xx_dss_dispc_hwmod = {
.slaves = omap44xx_dss_dispc_slaves,
.slaves_cnt = ARRAY_SIZE(omap44xx_dss_dispc_slaves),
.omap_chip = OMAP_CHIP_INIT(CHIP_IS_OMAP4430),
+ .dev_attr = &omap44xx_dss_dispc_dev_attr
};
/*
diff --git a/arch/arm/mach-omap2/omap_hwmod_common_data.c b/arch/arm/mach-omap2/omap_hwmod_common_data.c
index de832eb..51e5418 100644
--- a/arch/arm/mach-omap2/omap_hwmod_common_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_common_data.c
@@ -49,3 +49,7 @@ struct omap_hwmod_sysc_fields omap_hwmod_sysc_type2 = {
.srst_shift = SYSC_TYPE2_SOFTRESET_SHIFT,
};
+struct omap_dss_dispc_dev_attr omap2_3_dss_dispc_dev_attr = {
+ .manager_count = 2,
+ .has_framedonetv_irq = 0
+};
diff --git a/arch/arm/mach-omap2/omap_hwmod_common_data.h b/arch/arm/mach-omap2/omap_hwmod_common_data.h
index 39a7c37..ad5d8f0 100644
--- a/arch/arm/mach-omap2/omap_hwmod_common_data.h
+++ b/arch/arm/mach-omap2/omap_hwmod_common_data.h
@@ -16,6 +16,8 @@
#include <plat/omap_hwmod.h>
+#include "display.h"
+
/* Common address space across OMAP2xxx */
extern struct omap_hwmod_addr_space omap2xxx_uart1_addr_space[];
extern struct omap_hwmod_addr_space omap2xxx_uart2_addr_space[];
@@ -111,4 +113,6 @@ extern struct omap_hwmod_class omap2xxx_dma_hwmod_class;
extern struct omap_hwmod_class omap2xxx_mailbox_hwmod_class;
extern struct omap_hwmod_class omap2xxx_mcspi_class;
+extern struct omap_dss_dispc_dev_attr omap2_3_dss_dispc_dev_attr;
+
#endif
--
1.7.6.3
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