clk: renesas: rcar-gen3: Extend SDnH divider table
authorDirk Behme <dirk.behme@de.bosch.com>
Thu, 28 Sep 2023 08:03:17 +0000 (10:03 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 20 Nov 2023 10:51:56 +0000 (11:51 +0100)
commitf26a440d0ec15bda5ecfde82904dc27678642bed
tree0b5386bbb442068883ef7800c54797638cc0fec7
parentd72c586809e0f0fa045c7249a8988736c01af1dd
clk: renesas: rcar-gen3: Extend SDnH divider table

[ Upstream commit d5252d9697a3e7007c741e9c103073868955a304 ]

The clock dividers might be used with clock stop bit enabled or not.
Current tables only support recommended values from the datasheet.  This
might result in warnings like below because no valid clock divider is
found. Resulting in a 0 divider.

There are Renesas ARM Trusted Firmware version out there which e.g.
configure 0x201 (shifted logical right by 2: 0x80) and with this match
the added { STPnHCK | 0, 1 }:

https://github.com/renesas-rcar/arm-trusted-firmware/blob/rcar_gen3_v2.3/drivers/renesas/rcar/emmc/emmc_init.c#L108

------------[ cut here ]------------
sd1h: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set
WARNING: CPU: 1 PID: 1 at drivers/clk/clk-divider.c:141 divider_recalc_rate+0x48/0x70
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.1.52 #1
Hardware name: Custom board based on r8a7796 (DT)
pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : divider_recalc_rate+0x48/0x70
...
------------[ cut here ]------------

Fixes: bb6d3fa98a41 ("clk: renesas: rcar-gen3: Switch to new SD clock handling")
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
[wsa: extended the table to 5 entries, added comments, reword commit message a little]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230928080317.28224-1-wsa+renesas@sang-engineering.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/clk/renesas/rcar-cpg-lib.c