[PATCH v2 1/3] clk: renesas: cpg-mssr: add support for ignore-unused clocks

[Ulrich Hecht <uli+renesas@xxxxxxxx>]

This adds facilities to mark clocks as "ignore used", i.e. never to be
turned off. The primary application is the RWDT clock, which needs to
remain on throughout the boot process if enabled by the bootloader.

Signed-off-by: Ulrich Hecht <uli+renesas@xxxxxxxx>
---
 drivers/clk/renesas/renesas-cpg-mssr.c | 5 +++++
 drivers/clk/renesas/renesas-cpg-mssr.h | 9 +++++++++
 2 files changed, 14 insertions(+)

diff --git a/drivers/clk/renesas/renesas-cpg-mssr.c b/drivers/clk/renesas/renesas-cpg-mssr.c
index a2663fb..046efc9 100644
--- a/drivers/clk/renesas/renesas-cpg-mssr.c
+++ b/drivers/clk/renesas/renesas-cpg-mssr.c
@@ -423,6 +423,11 @@ static void __init cpg_mssr_register_mod_clk(const struct mssr_mod_clk *mod,
 			init.flags |= CLK_IS_CRITICAL;
 			break;
 		}
+	for (i = 0; i < info->num_ignore_unused_mod_clks; i++)
+		if (id == info->ignore_unused_mod_clks[i]) {
+			init.flags |= CLK_IGNORE_UNUSED;
+			break;
+		}
 
 	parent_name = __clk_get_name(parent);
 	init.parent_names = &parent_name;
diff --git a/drivers/clk/renesas/renesas-cpg-mssr.h b/drivers/clk/renesas/renesas-cpg-mssr.h
index 3b852ba..2a4b47e 100644
--- a/drivers/clk/renesas/renesas-cpg-mssr.h
+++ b/drivers/clk/renesas/renesas-cpg-mssr.h
@@ -105,6 +105,11 @@ struct device_node;
      * @crit_mod_clks: Array with Module Clock IDs of critical clocks that
      *                 should not be disabled without a knowledgeable driver
      * @num_crit_mod_clks: Number of entries in crit_mod_clks[]
+     * @ignore_unused_mod_clks: Array with Module Clock IDs of clocks that
+     *                          should not be disabled even if they seem to
+     *                          be unused
+     * @num_ignore_unused_mod_clks: Number of entries in
+     *                              ignore_unused_mod_clks[]
      *
      * @core_pm_clks: Array with IDs of Core Clocks that are suitable for Power
      *                Management, in addition to Module Clocks
@@ -141,6 +146,10 @@ struct cpg_mssr_info {
 	const unsigned int *crit_mod_clks;
 	unsigned int num_crit_mod_clks;
 
+	/* Module Clocks that should not be disabled even if unused */
+	const unsigned int *ignore_unused_mod_clks;
+	unsigned int num_ignore_unused_mod_clks;
+
 	/* Core Clocks suitable for PM, in addition to the Module Clocks */
 	const unsigned int *core_pm_clks;
 	unsigned int num_core_pm_clks;
-- 
2.7.4