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: bb6d3fa98a ("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>
d5252d9697