Re: [PATCH v1 5/6] clk: microchip: mpfs: fix criticality of peripheral clocks

[<Padmarao.Begari@microchip.com>]

> On Tue, 2022-10-25 at 08:58 +0100, Conor Dooley wrote:
> Sync the critical clocks in the U-Boot driver with those marked as
> critical in Linux. The Linux driver has an explanation of why each
> clock
> is considered to be critical, so import that too.
> 
> Fixes: 2f27c9219e ("clk: Add Microchip PolarFire SoC clock driver")
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
>  drivers/clk/microchip/mpfs_clk_periph.c | 28 ++++++++++++++++++-----
> --
>  1 file changed, 21 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/clk/microchip/mpfs_clk_periph.c
> b/drivers/clk/microchip/mpfs_clk_periph.c
> index e23eb552c3..ddeccb9145 100644
> --- a/drivers/clk/microchip/mpfs_clk_periph.c
> +++ b/drivers/clk/microchip/mpfs_clk_periph.c
> @@ -114,13 +114,27 @@ static ulong mpfs_periph_clk_recalc_rate(struct
> clk *hw)
>  		.periph.flags = _flags,			\
>  	}
>  
> +/*
> + * Critical clocks:
> + * - CLK_ENVM: reserved by hart software services (hss) superloop
> monitor/m mode interrupt
> + *   trap handler
> + * - CLK_MMUART0: reserved by the hss
> + * - CLK_DDRC: provides clock to the ddr subsystem
> + * - CLK_RTC: the onboard RTC's AHB bus clock must be kept running
> as the rtc will stop
> + *   if the AHB interface clock is disabled
> + * - CLK_FICx: these provide the processor side clocks to the "FIC"
> (Fabric InterConnect)
> + *   clock domain crossers which provide the interface to the FPGA
> fabric. Disabling them
> + *   causes the FPGA fabric to go into reset.
> + * - CLK_ATHENA: The athena clock is FIC4, which is reserved for the
> Athena TeraFire.
> + */
> +
>  static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
>  	CLK_PERIPH(CLK_ENVM, "clk_periph_envm", CLK_AHB, 0,
> CLK_IS_CRITICAL),
>  	CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", CLK_AHB, 1, 0),
>  	CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", CLK_AHB, 2, 0),
>  	CLK_PERIPH(CLK_MMC, "clk_periph_mmc", CLK_AHB, 3, 0),
>  	CLK_PERIPH(CLK_TIMER, "clk_periph_timer", CLK_RTCREF, 4, 0),
> -	CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", CLK_AHB, 5, 0),
> +	CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", CLK_AHB, 5,
> CLK_IS_CRITICAL),
>  	CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", CLK_AHB, 6, 0),
>  	CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", CLK_AHB, 7, 0),
>  	CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", CLK_AHB, 8, 0),
> @@ -132,17 +146,17 @@ static struct mpfs_periph_hw_clock
> mpfs_periph_clks[] = {
>  	CLK_PERIPH(CLK_CAN0, "clk_periph_can0", CLK_AHB, 14, 0),
>  	CLK_PERIPH(CLK_CAN1, "clk_periph_can1", CLK_AHB, 15, 0),
>  	CLK_PERIPH(CLK_USB, "clk_periph_usb", CLK_AHB, 16, 0),
> -	CLK_PERIPH(CLK_RTC, "clk_periph_rtc", CLK_AHB, 18, 0),
> +	CLK_PERIPH(CLK_RTC, "clk_periph_rtc", CLK_AHB, 18,
> CLK_IS_CRITICAL),
>  	CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", CLK_AHB, 19, 0),
>  	CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", CLK_AHB, 20, 0),
>  	CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", CLK_AHB, 21, 0),
>  	CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", CLK_AHB, 22, 0),
>  	CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", CLK_AHB, 23,
> CLK_IS_CRITICAL),
> -	CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", CLK_AXI, 24, 0),
> -	CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", CLK_AXI, 25, 0),
> -	CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", CLK_AXI, 26, 0),
> -	CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", CLK_AXI, 27, 0),
> -	CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", CLK_AXI, 28, 0),
> +	CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", CLK_AXI, 24,
> CLK_IS_CRITICAL),
> +	CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", CLK_AXI, 25,
> CLK_IS_CRITICAL),
> +	CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", CLK_AXI, 26,
> CLK_IS_CRITICAL),
> +	CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", CLK_AXI, 27,
> CLK_IS_CRITICAL),
> +	CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", CLK_AXI, 28,
> CLK_IS_CRITICAL),
>  	CLK_PERIPH(CLK_CFM, "clk_periph_cfm", CLK_AHB, 29, 0),
>  };
>  

Reviewed-by: Padmarao Begari <padmarao.begari@microchip.com>