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mfd: rz-mtu3: Reduce critical sections

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Reduce critical sections on rz_mtu3_start_stop_ch() and
rz_mtu3_is_enabled() by moving offset and bitpos computation
outside the critical section and drop the 'ret' variable on
rz_mtu3_is_enabled() and return 'tstr & BIT(bitpos)' directly.

Reported-by: Pavel Machek <pavel@denx.de>
Closes: https://lore.kernel.org/all/ZIMAse1ikTuycJ02@duo.ucw.cz/
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Pavel Machek <pavel@denx.de>
Link: https://lore.kernel.org/r/20230815073445.9579-2-biju.das.jz@bp.renesas.com
Signed-off-by: Lee Jones <lee@kernel.org>
This commit is contained in:
Biju Das 2023-08-15 08:34:44 +01:00 committed by Lee Jones
parent 367124ebb3
commit a160d1286b
1 changed files with 7 additions and 9 deletions
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16
drivers/mfd/rz-mtu3.c
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@ -252,11 +252,12 @@ static void rz_mtu3_start_stop_ch(struct rz_mtu3_channel *ch, bool start)
u16 offset;
u8 bitpos;
offset = rz_mtu3_get_tstr_offset(ch);
bitpos = rz_mtu3_get_tstr_bit_pos(ch);
/* start stop register shared by multiple timer channels */
raw_spin_lock_irqsave(&priv->lock, flags);
offset = rz_mtu3_get_tstr_offset(ch);
bitpos = rz_mtu3_get_tstr_bit_pos(ch);
tstr = rz_mtu3_shared_reg_read(ch, offset);
__assign_bit(bitpos, &tstr, start);
rz_mtu3_shared_reg_write(ch, offset, tstr);
@ -269,21 +270,18 @@ bool rz_mtu3_is_enabled(struct rz_mtu3_channel *ch)
struct rz_mtu3 *mtu = dev_get_drvdata(ch->dev->parent);
struct rz_mtu3_priv *priv = mtu->priv_data;
unsigned long flags, tstr;
bool ret = false;
u16 offset;
u8 bitpos;
/* start stop register shared by multiple timer channels */
raw_spin_lock_irqsave(&priv->lock, flags);
offset = rz_mtu3_get_tstr_offset(ch);
bitpos = rz_mtu3_get_tstr_bit_pos(ch);
tstr = rz_mtu3_shared_reg_read(ch, offset);
ret = tstr & BIT(bitpos);
/* start stop register shared by multiple timer channels */
raw_spin_lock_irqsave(&priv->lock, flags);
tstr = rz_mtu3_shared_reg_read(ch, offset);
raw_spin_unlock_irqrestore(&priv->lock, flags);
return ret;
return tstr & BIT(bitpos);
}
EXPORT_SYMBOL_GPL(rz_mtu3_is_enabled);