[PATCH v6 09/17] clk: sifive: fu540-prci: Add clock initialization for SPL

Bin Meng bmeng.cn at gmail.com
Fri Apr 24 15:00:35 CEST 2020


Hi Pragnesh,

On Fri, Apr 24, 2020 at 6:08 PM Pragnesh Patel
<pragnesh.patel at sifive.com> wrote:
>
> Hi Bin, Jagan
>
> >-----Original Message-----
> >From: Bin Meng <bmeng.cn at gmail.com>
> >Sent: 20 April 2020 14:30
> >To: Jagan Teki <jagan at amarulasolutions.com>
> >Cc: Pragnesh Patel <pragnesh.patel at sifive.com>; U-Boot-Denx <u-
> >boot at lists.denx.de>; Atish Patra <atish.patra at wdc.com>; Palmer Dabbelt
> ><palmerdabbelt at google.com>; Paul Walmsley <paul.walmsley at sifive.com>;
> >Troy Benjegerdes <troy.benjegerdes at sifive.com>; Anup Patel
> ><anup.patel at wdc.com>; Sagar Kadam <sagar.kadam at sifive.com>; Rick Chen
> ><rick at andestech.com>; Lukasz Majewski <lukma at denx.de>; Simon Glass
> ><sjg at chromium.org>
> >Subject: Re: [PATCH v6 09/17] clk: sifive: fu540-prci: Add clock initialization for
> >SPL
> >
> >[External Email] Do not click links or attachments unless you recognize the
> >sender and know the content is safe
> >
> >Hi Jagan, Pragnesh,
> >
> >On Tue, Apr 7, 2020 at 3:35 AM Jagan Teki <jagan at amarulasolutions.com>
> >wrote:
> >>
> >> On Sun, Mar 29, 2020 at 10:37 PM Pragnesh Patel
> >> <pragnesh.patel at sifive.com> wrote:
> >> >
> >> > Set corepll, ddrpll and ethernet PLL for u-boot-spl
> >> >
> >> > Signed-off-by: Pragnesh Patel <pragnesh.patel at sifive.com>
> >> > ---
> >> >  drivers/clk/sifive/fu540-prci.c | 118
> >> > ++++++++++++++++++++++++++++++++
> >> >  1 file changed, 118 insertions(+)
> >> >
> >> > diff --git a/drivers/clk/sifive/fu540-prci.c
> >> > b/drivers/clk/sifive/fu540-prci.c index e6214cd821..3a73c2c8d1
> >> > 100644
> >> > --- a/drivers/clk/sifive/fu540-prci.c
> >> > +++ b/drivers/clk/sifive/fu540-prci.c
> >> > @@ -41,6 +41,10 @@
> >> >  #include <linux/clk/analogbits-wrpll-cln28hpc.h>
> >> >  #include <dt-bindings/clock/sifive-fu540-prci.h>
> >> >
> >> > +#define DDRCTLPLL_F    55
> >> > +#define DDRCTLPLL_Q    2
> >> > +#define MHz            1000000
> >> > +
> >> >  /*
> >> >   * EXPECTED_CLK_PARENT_COUNT: how many parent clocks this driver
> >expects:
> >> >   *     hfclk and rtcclk
> >> > @@ -152,6 +156,27 @@
> >> >  #define PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_MASK \
> >> >                         (0x1 <<
> >> > PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_SHIFT)
> >> >
> >> > +/* PROCMONCFG */
> >> > +#define PRCI_PROCMONCFG_OFFSET                 0xF0
> >> > +#define PRCI_PROCMONCFG_CORE_CLOCK_SHIFT       24
> >> > +#define PRCI_PROCMONCFG_CORE_CLOCK_MASK \
> >> > +                       (0x1 << PRCI_PROCMONCFG_CORE_CLOCK_SHIFT)
> >> > +
> >> > +#define PLL_R(x) \
> >> > +       ((x) << PRCI_DDRPLLCFG0_DIVR_SHIFT) &
> >> > +PRCI_DDRPLLCFG0_DIVR_MASK #define PLL_F(x) \
> >> > +       ((x) << PRCI_DDRPLLCFG0_DIVF_SHIFT) &
> >> > +PRCI_DDRPLLCFG0_DIVF_MASK #define PLL_Q(x) \
> >> > +       ((x) << PRCI_DDRPLLCFG0_DIVQ_SHIFT) &
> >> > +PRCI_DDRPLLCFG0_DIVQ_MASK #define PLL_RANGE(x) \
> >> > +       ((x) << PRCI_DDRPLLCFG0_RANGE_SHIFT) &
> >> > +PRCI_DDRPLLCFG0_RANGE_MASK #define PLL_BYPASS(x) \
> >> > +       ((x) << PRCI_DDRPLLCFG0_BYPASS_SHIFT) &
> >> > +PRCI_DDRPLLCFG0_BYPASS_MASK #define PLL_FSE(x) \
> >> > +       ((x) << PRCI_DDRPLLCFG0_FSE_SHIFT) &
> >> > +PRCI_DDRPLLCFG0_FSE_MASK #define PLL_LOCK(x) \
> >> > +       ((x) << PRCI_DDRPLLCFG0_LOCK_SHIFT) &
> >> > +PRCI_DDRPLLCFG0_LOCK_MASK
> >> > +
> >> >  /*
> >> >   * Private structures
> >> >   */
> >> > @@ -654,6 +679,93 @@ static int sifive_fu540_prci_disable(struct clk *clk)
> >> >         return pc->ops->enable_clk(pc, 0);  }
> >> >
> >> > +#ifdef CONFIG_SPL_BUILD
> >> > +static void corepll_init(struct udevice *dev) {
> >> > +       u32 v;
> >> > +       struct clk clock;
> >> > +       struct __prci_data *pd = dev_get_priv(dev);
> >> > +
> >> > +       v = __prci_readl(pd, PRCI_CLKMUXSTATUSREG_OFFSET);
> >> > +       v &= PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_MASK;
> >> > +
> >> > +       clock.id = PRCI_CLK_COREPLL;
> >> > +
> >> > +       if (v) {
> >> > +               /* corepll 500 Mhz */
> >> > +               sifive_fu540_prci_set_rate(&clock, 500UL * MHz);
> >> > +       } else {
> >> > +               /* corepll 1 Ghz */
> >> > +               sifive_fu540_prci_set_rate(&clock, 1000UL * MHz);
> >> > +       }
> >> > +
> >> > +
> >> > +sifive_fu540_prci_clock_enable(&__prci_init_clocks[clock.id], 1); }
> >> > +
> >> > +static void ddr_init(struct udevice *dev) {
> >> > +       u32 v;
> >> > +       struct clk clock;
> >> > +       struct __prci_data *pd = dev_get_priv(dev);
> >> > +
> >> > +       //DDR init
> >> > +       u32 ddrctlmhz =
> >> > +               (PLL_R(0)) |
> >> > +               (PLL_F(DDRCTLPLL_F)) |
> >> > +               (PLL_Q(DDRCTLPLL_Q)) |
> >> > +               (PLL_RANGE(0x4)) |
> >> > +               (PLL_BYPASS(0)) |
> >> > +               (PLL_FSE(1));
> >> > +       __prci_writel(ddrctlmhz, PRCI_DDRPLLCFG0_OFFSET, pd);
> >> > +
> >> > +       clock.id = PRCI_CLK_DDRPLL;
> >> > +
> >> > + sifive_fu540_prci_clock_enable(&__prci_init_clocks[clock.id], 1);
> >> > +
> >> > +       /* Release DDR reset */
> >> > +       v = __prci_readl(pd, PRCI_DEVICESRESETREG_OFFSET);
> >> > +       v |= PRCI_DEVICESRESETREG_DDR_CTRL_RST_N_MASK;
> >> > +       __prci_writel(v, PRCI_DEVICESRESETREG_OFFSET, pd);
> >> > +
> >> > +       // HACK to get the '1 full controller clock cycle'.
> >> > +       asm volatile ("fence");
> >> > +       v = __prci_readl(pd, PRCI_DEVICESRESETREG_OFFSET);
> >> > +       v |= (PRCI_DEVICESRESETREG_DDR_AXI_RST_N_MASK |
> >> > +             PRCI_DEVICESRESETREG_DDR_AHB_RST_N_MASK |
> >> > +             PRCI_DEVICESRESETREG_DDR_PHY_RST_N_MASK);
> >> > +       __prci_writel(v, PRCI_DEVICESRESETREG_OFFSET, pd);
> >> > +       // HACK to get the '1 full controller clock cycle'.
> >> > +       asm volatile ("fence");
> >> > +
> >> > +       /* These take like 16 cycles to actually propagate. We can't go sending
> >> > +        * stuff before they come out of reset. So wait. (TODO: Add a register
> >> > +        * to read the current reset states, or DDR Control device?)
> >> > +        */
> >> > +       for (int i = 0; i < 256; i++)
> >> > +               asm volatile ("nop"); }
> >> > +
> >> > +static void ethernet_init(struct udevice *dev) {
> >> > +       u32 v;
> >> > +       struct clk clock;
> >> > +       struct __prci_data *pd = dev_get_priv(dev);
> >> > +
> >> > +       /* GEMGXL init */
> >> > +       clock.id = PRCI_CLK_GEMGXLPLL;
> >> > +       sifive_fu540_prci_set_rate(&clock, 125UL * MHz);
> >> > +
> >> > + sifive_fu540_prci_clock_enable(&__prci_init_clocks[clock.id], 1);
> >> > +
> >> > +       /* Release GEMGXL reset */
> >> > +       v = __prci_readl(pd, PRCI_DEVICESRESETREG_OFFSET);
> >> > +       v |= PRCI_DEVICESRESETREG_GEMGXL_RST_N_MASK;
> >> > +       __prci_writel(v, PRCI_DEVICESRESETREG_OFFSET, pd);
> >> > +
> >> > +       /* Procmon => core clock */
> >> > +       __prci_writel(PRCI_PROCMONCFG_CORE_CLOCK_MASK,
> >PRCI_PROCMONCFG_OFFSET,
> >> > +                     pd);
> >> > +}
> >> > +#endif
> >> > +
> >> >  static int sifive_fu540_prci_probe(struct udevice *dev)  {
> >> >         int i, err;
> >> > @@ -679,6 +791,12 @@ static int sifive_fu540_prci_probe(struct udevice
> >*dev)
> >> >                         __prci_wrpll_read_cfg0(pd, pc->pwd);
> >> >         }
> >> >
> >> > +#ifdef CONFIG_SPL_BUILD
> >> > +       corepll_init(dev);
> >> > +       ddr_init(dev);
> >> > +       ethernet_init(dev);
> >> > +#endif
> >>
> >> 1. Why would ethernet clocks require for SPL 2. Why these clocks are
> >> special for SPL, can't we use it for U-Boot proper 3. This look like
> >> raw clock initialization instead of having in conventional dm way.
> >> since these are here just to use pd.  May be reuse the required clock
> >> of what u-boot proper using or move them into spl code.
>
> 1. ethernet clock is not necessary for SPL but SPL performs ethernet PHY reset
> sequence (board/sifive/fu540/spl.c - "gem_phy_reset") and for that ethernet clock needs to be enabled.

Can we delay that for U-Boot proper to enable PRCI ethernet clock and
reset the PHY ?

>
> 2. There is nothing special of this clocks for SPL, we can use this for U-Boot.
> I am planning to add this clocks in device tree but I am not sure how to add coreclk (corepll) in device tree
> Do you guys have any suggestion for this ?
>

Does the example in
http://patchwork.ozlabs.org/project/uboot/patch/20200423023320.1380090-20-seanga2@gmail.com/
help?

+ cpu0: cpu at 0 {
+ device_type = "cpu";
+ compatible = "kendryte,k210", "sifive,rocket0", "riscv";
+ reg = <0>;
+ riscv,isa = "rv64imafdgc";
+ mmu-type = "sv39";
+ i-cache-block-size = <64>;
+ i-cache-size = <0x8000>;
+ d-cache-block-size = <64>;
+ d-cache-size = <0x8000>;
+ clocks = <&sysclk K210_CLK_CPU>;

You need this patch to get clock in the CPU node.

http://patchwork.ozlabs.org/project/uboot/patch/20200423023320.1380090-19-seanga2@gmail.com/

> 3. I am planning to make dm way.
>
> Any suggestions are welcome
>
> >
> >I believe Jagan's comments are the same as mine that was mentioned in
> >previous version:
> >
> >See
> >https://patchwork.ozlabs.org/project/uboot/patch/20200311070320.21323-
> >10-pragnesh.patel at sifive.com/
> >

Regards,
Bin


More information about the U-Boot mailing list