[PATCH] pinctrl: pinctrl-single: Avoid divisions in context save/restore
From: geert+renesas@glider.be (Geert Uytterhoeven)
Date: 2018-06-07 12:24:34
Also in:
linux-gpio, linux-omap
Subsystem:
pin control subsystem, pin controller - single, the rest · Maintainers:
Linus Walleij, Tony Lindgren, Haojian Zhuang, Linus Torvalds
The divisions (and multiplications) can be avoided by changing the loops to use increments of mux_bytes instead of 1. While at it, remove the unneeded casts when assigning void pointers. This saves +100 bytes of kernel size on arm32/arm64. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- Compile-tested only. As the loops are now identical, the code could be made even smaller by moving the switch() inside the loop, at the expense of readability. --- drivers/pinctrl/pinctrl-single.c | 36 ++++++++++++++++++------------------ 1 file changed, 18 insertions(+), 18 deletions(-)
diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index 9c3c00515aa0fe20..5de5dedb804928eb 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c@@ -1593,19 +1593,19 @@ static int pcs_save_context(struct pcs_device *pcs) switch (pcs->width) { case 64: - regsl = (u64 *)pcs->saved_vals; - for (i = 0; i < pcs->size / mux_bytes; i++) - regsl[i] = pcs->read(pcs->base + i * mux_bytes); + regsl = pcs->saved_vals; + for (i = 0; i < pcs->size; i += mux_bytes) + *regsl++ = pcs->read(pcs->base + i); break; case 32: - regsw = (u32 *)pcs->saved_vals; - for (i = 0; i < pcs->size / mux_bytes; i++) - regsw[i] = pcs->read(pcs->base + i * mux_bytes); + regsw = pcs->saved_vals; + for (i = 0; i < pcs->size; i += mux_bytes) + *regsw++ = pcs->read(pcs->base + i); break; case 16: - regshw = (u16 *)pcs->saved_vals; - for (i = 0; i < pcs->size / mux_bytes; i++) - regshw[i] = pcs->read(pcs->base + i * mux_bytes); + regshw = pcs->saved_vals; + for (i = 0; i < pcs->size; i += mux_bytes) + *regshw++ = pcs->read(pcs->base + i); break; }
@@ -1623,19 +1623,19 @@ static void pcs_restore_context(struct pcs_device *pcs) switch (pcs->width) { case 64: - regsl = (u64 *)pcs->saved_vals; - for (i = 0; i < pcs->size / mux_bytes; i++) - pcs->write(regsl[i], pcs->base + i * mux_bytes); + regsl = pcs->saved_vals; + for (i = 0; i < pcs->size; i += mux_bytes) + pcs->write(*regsl++, pcs->base + i); break; case 32: - regsw = (u32 *)pcs->saved_vals; - for (i = 0; i < pcs->size / mux_bytes; i++) - pcs->write(regsw[i], pcs->base + i * mux_bytes); + regsw = pcs->saved_vals; + for (i = 0; i < pcs->size; i += mux_bytes) + pcs->write(*regsw++, pcs->base + i); break; case 16: - regshw = (u16 *)pcs->saved_vals; - for (i = 0; i < pcs->size / mux_bytes; i++) - pcs->write(regshw[i], pcs->base + i * mux_bytes); + regshw = pcs->saved_vals; + for (i = 0; i < pcs->size; i += mux_bytes) + pcs->write(*regshw++, pcs->base + i); break; } }
--
2.7.4