pinctrl: renesas: checker: Add reserved field checks
Add checks for discovering registers with reserved fields that could
benefit from being described using variable-width reserved field
shorthands, reducing kernel size.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/f5a5159ba7b396e6f09dd3f23c864a74ed8e342d.1649865241.git.geert+renesas@glider.be
diff --git a/drivers/pinctrl/renesas/core.c b/drivers/pinctrl/renesas/core.c
index ec88fe86..8c14b20 100644
--- a/drivers/pinctrl/renesas/core.c
+++ b/drivers/pinctrl/renesas/core.c
@@ -877,7 +877,7 @@
static void __init sh_pfc_check_cfg_reg(const char *drvname,
const struct pinmux_cfg_reg *cfg_reg)
{
- unsigned int i, n, rw;
+ unsigned int i, n, rw, r;
int fw;
sh_pfc_check_reg(drvname, cfg_reg->reg,
@@ -886,6 +886,15 @@
if (cfg_reg->field_width) {
fw = cfg_reg->field_width;
n = (cfg_reg->reg_width / fw) << fw;
+ for (i = 0, r = 0; i < n; i += 1 << fw) {
+ if (is0s(&cfg_reg->enum_ids[i], 1 << fw))
+ r++;
+ }
+
+ if ((r << fw) * sizeof(u16) > cfg_reg->reg_width / fw)
+ sh_pfc_warn("reg 0x%x can be described with variable-width reserved fields\n",
+ cfg_reg->reg);
+
/* Skip field checks (done at build time) */
goto check_enum_ids;
}
