ARM: OMAP2+: hwmod: Add support for per hwmod/module context lost count

OMAP4 has module specific context lost registers which makes it now
possible to have module level context loss count, instead of relying
on the powerdomain level context count.

Add 2 private hwmod api's to update/clear the hwmod/module specific
context lost counters/register.

Update the module specific context_lost_counter and clear the hardware
bits just after enabling the module.

omap_hwmod_get_context_loss_count() now returns the hwmod context loss
count them on platforms where they exist (OMAP4), else fall back on
the pwrdm level counters for older platforms.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
[paul@pwsan.com: added function kerneldoc, fixed structure kerneldoc,
 rearranged structure to avoid memory waste, marked fns as OMAP4-specific,
 prevent fn entry on non-OMAP4 chips, reduced indentation, merged update
 and clear, merged patches]
[t-kristo@ti.com: added support for arch specific hwmod ops, and changed
 the no context offset indicator to USHRT_MAX]
Signed-off-by: Tero Kristo <t-kristo@ti.com>
[paul@pwsan.com: use NO_CONTEXT_LOSS_BIT flag rather than USHRT_MAX;
 convert unsigned context lost counter to int to match the return type;
 get rid of hwmod_ops in favor of the existing soc_ops mechanism;
 move context loss low-level accesses to the PRM code]
Signed-off-by: Paul Walmsley <paul@pwsan.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/prm44xx.c b/arch/arm/mach-omap2/prm44xx.c
index 9db1bd279f8e..7498bc77fe8b 100644
--- a/arch/arm/mach-omap2/prm44xx.c
+++ b/arch/arm/mach-omap2/prm44xx.c
@@ -346,6 +346,37 @@ static u32 omap44xx_prm_read_reset_sources(void)
 	return r;
 }
 
+/**
+ * omap44xx_prm_was_any_context_lost_old - was module hardware context lost?
+ * @part: PRM partition ID (e.g., OMAP4430_PRM_PARTITION)
+ * @inst: PRM instance offset (e.g., OMAP4430_PRM_MPU_INST)
+ * @idx: CONTEXT register offset
+ *
+ * Return 1 if any bits were set in the *_CONTEXT_* register
+ * identified by (@part, @inst, @idx), which means that some context
+ * was lost for that module; otherwise, return 0.
+ */
+static bool omap44xx_prm_was_any_context_lost_old(u8 part, s16 inst, u16 idx)
+{
+	return (omap4_prminst_read_inst_reg(part, inst, idx)) ? 1 : 0;
+}
+
+/**
+ * omap44xx_prm_clear_context_lost_flags_old - clear context loss flags
+ * @part: PRM partition ID (e.g., OMAP4430_PRM_PARTITION)
+ * @inst: PRM instance offset (e.g., OMAP4430_PRM_MPU_INST)
+ * @idx: CONTEXT register offset
+ *
+ * Clear hardware context loss bits for the module identified by
+ * (@part, @inst, @idx).  No return value.  XXX Writes to reserved bits;
+ * is there a way to avoid this?
+ */
+static void omap44xx_prm_clear_context_loss_flags_old(u8 part, s16 inst,
+						      u16 idx)
+{
+	omap4_prminst_write_inst_reg(0xffffffff, part, inst, idx);
+}
+
 /* Powerdomain low-level functions */
 
 static int omap4_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
@@ -613,6 +644,8 @@ struct pwrdm_ops omap4_pwrdm_operations = {
  */
 static struct prm_ll_data omap44xx_prm_ll_data = {
 	.read_reset_sources = &omap44xx_prm_read_reset_sources,
+	.was_any_context_lost_old = &omap44xx_prm_was_any_context_lost_old,
+	.clear_context_loss_flags_old = &omap44xx_prm_clear_context_loss_flags_old,
 };
 
 int __init omap44xx_prm_init(void)