@@ -360,7 +360,7 @@ static int _set_clockactivity(struct omap_hwmod *oh, u8 clockact, u32 *v)
}
/**
- * _set_softreset: set OCP_SYSCONFIG.CLOCKACTIVITY bits in @v
+ * _set_softreset: set OCP_SYSCONFIG.SOFTRESET bit in @v
* @oh: struct omap_hwmod *
* @v: pointer to register contents to modify
*
@@ -388,6 +388,36 @@ static int _set_softreset(struct omap_hwmod *oh, u32 *v)
}
/**
+ * _clear_softreset: clear OCP_SYSCONFIG.SOFTRESET bit in @v
+ * @oh: struct omap_hwmod *
+ * @v: pointer to register contents to modify
+ *
+ * Clear the SOFTRESET bit in @v for hwmod @oh. Returns -EINVAL upon
+ * error or 0 upon success.
+ */
+static int _clear_softreset(struct omap_hwmod *oh, u32 *v)
+{
+ u32 softrst_mask;
+
+ if (!oh->class->sysc ||
+ !(oh->class->sysc->sysc_flags & SYSC_HAS_SOFTRESET))
+ return -EINVAL;
+
+ if (!oh->class->sysc->sysc_fields) {
+ WARN(1,
+ "omap_hwmod: %s: sysc_fields absent for sysconfig class\n",
+ oh->name);
+ return -EINVAL;
+ }
+
+ softrst_mask = (0x1 << oh->class->sysc->sysc_fields->srst_shift);
+
+ *v &= ~softrst_mask;
+
+ return 0;
+}
+
+/**
* _set_module_autoidle: set the OCP_SYSCONFIG AUTOIDLE field in @v
* @oh: struct omap_hwmod *
* @autoidle: desired AUTOIDLE bitfield value (0 or 1)
@@ -1655,6 +1685,12 @@ static int _ocp_softreset(struct omap_hwmod *oh)
ret = _set_softreset(oh, &v);
if (ret)
goto dis_opt_clks;
+
+ _write_sysconfig(v, oh);
+ ret = _clear_softreset(oh, &v);
+ if (ret)
+ goto dis_opt_clks;
+
_write_sysconfig(v, oh);
if (oh->class->sysc->srst_udelay)
@@ -2488,6 +2524,11 @@ int omap_hwmod_softreset(struct omap_hwmod *oh)
goto error;
_write_sysconfig(v, oh);
+ ret = _clear_softreset(oh, &v);
+ if (ret)
+ goto error;
+ _write_sysconfig(v, oh);
+
error:
return ret;
}
This is a note to let you know that I have just added a patch titled ARM: OMAP2+: hwmod: Fix SOFTRESET logic to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 68e4c6f889101746c115502626780f33fd3658c1 Mon Sep 17 00:00:00 2001 From: Roger Quadros <rogerq@ti.com> Date: Sun, 8 Dec 2013 18:39:02 -0700 Subject: ARM: OMAP2+: hwmod: Fix SOFTRESET logic commit 313a76ee11cda6700548afe68499ef174a240688 upstream. In _ocp_softreset(), after _set_softreset() + write_sysconfig(), the hwmod's sysc_cache will always contain SOFTRESET bit set so all further writes to sysconfig using this cache will initiate a repeated SOFTRESET e.g. enable_sysc(). This is true for OMAP3 like platforms that have RESET_DONE status in the SYSSTATUS register and so the the SOFTRESET bit in SYSCONFIG is not automatically cleared. It is not a problem for OMAP4 like platforms that indicate RESET completion by clearing the SOFTRESET bit in the SYSCONFIG register. This repeated SOFTRESET is undesired and was the root cause of USB host issues on OMAP3 platforms when hwmod was allowed to do the SOFTRESET for the USB Host module. To fix this we clear the SOFTRESET bit and update the sysconfig register + sysc_cache using write_sysconfig(). Signed-off-by: Roger Quadros <rogerq@ti.com> Tested-by: Tomi Valkeinen <tomi.valkeinen@ti.com> # Panda, BeagleXM [paul@pwsan.com: renamed _clr_softreset() to _clear_softreset()] Signed-off-by: Paul Walmsley <paul@pwsan.com> [ luis: backported to 3.5: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/arm/mach-omap2/omap_hwmod.c | 43 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 42 insertions(+), 1 deletion(-) -- 1.8.3.2