Re: [PATCH 2/4] pinctrl: sh-pfc: Store register/field widths in u8 instead of unsigned long
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Date: 2015-03-05 09:03:23
Also in:
linux-sh
Hi Geert, Thank you for the patch. On Friday 27 February 2015 18:38:03 Geert Uytterhoeven wrote:
quoted hunk ↗ jump to hunk
Register and field widths are in the range 1..32. Storing them in the pinctrl data in (arrays of) unsigned long wastes space. This decreases the size of a (32-bit) shmobile_defconfig kernel supporting 7 SoCs by 26460 bytes. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- drivers/pinctrl/sh-pfc/core.c | 2 +- drivers/pinctrl/sh-pfc/sh_pfc.h | 10 ++++++---- 2 files changed, 7 insertions(+), 5 deletions(-)diff --git a/drivers/pinctrl/sh-pfc/core.c b/drivers/pinctrl/sh-pfc/core.c index a56280814a3f884b..466b899ec78b15d7 100644 --- a/drivers/pinctrl/sh-pfc/core.c +++ b/drivers/pinctrl/sh-pfc/core.c@@ -210,7 +210,7 @@ static void sh_pfc_write_config_reg(struct sh_pfc *pfc, sh_pfc_config_reg_helper(pfc, crp, field, &mapped_reg, &mask, &pos); dev_dbg(pfc->dev, "write_reg addr = %lx, value = %ld, field = %ld, " - "r_width = %ld, f_width = %ld\n", + "r_width = %u, f_width = %u\n", crp->reg, value, field, crp->reg_width, crp->field_width); mask = ~(mask << pos);diff --git a/drivers/pinctrl/sh-pfc/sh_pfc.hb/drivers/pinctrl/sh-pfc/sh_pfc.h index ed5cf4192fa1a2d0..6aeec8152ea674cf 100644--- a/drivers/pinctrl/sh-pfc/sh_pfc.h +++ b/drivers/pinctrl/sh-pfc/sh_pfc.h@@ -69,9 +69,10 @@ struct pinmux_func { }; struct pinmux_cfg_reg { - unsigned long reg, reg_width, field_width; + unsigned long reg;
How about making reg a u32 ? It won't make a difference in practice on 32-bit systems, but it would be more explicit. We could also save space by making reg a u16 and storing the register offset only instead of the full address (assuming it can always fit in 16 bits, which should be checked). We'll also need to support 64-bit systems at some point, and making reg a u64 would increase space waste.
quoted hunk ↗ jump to hunk
+ u8 reg_width, field_width; const u16 *enum_ids; - const unsigned long *var_field_width; + const u8 *var_field_width; }; #define PINMUX_CFG_REG(name, r, r_width, f_width) \@@ -80,12 +81,13 @@ struct pinmux_cfg_reg { #define PINMUX_CFG_REG_VAR(name, r, r_width, var_fw0, var_fwn...) \ .reg = r, .reg_width = r_width, \ - .var_field_width = (const unsigned long [r_width]) \ + .var_field_width = (const u8 [r_width]) \ { var_fw0, var_fwn, 0 }, \ .enum_ids = (const u16 []) struct pinmux_data_reg { - unsigned long reg, reg_width; + unsigned long reg; + u8 reg_width; const u16 *enum_ids; };
-- Regards, Laurent Pinchart