Messages in this thread | | | Subject | Re: [PATCH v2 3/5] clk: aspeed: Add platform driver and register PLLs | From | Andrew Jeffery <> | Date | Mon, 25 Sep 2017 22:10:55 +0930 |
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On Thu, 2017-09-21 at 13:56 +0930, Joel Stanley wrote: > This registers a platform driver to set up all of the non-core clocks. > > The clocks that have configurable rates are now registered. > > Signed-off-by: Joel Stanley <joel@jms.id.au> > --- > drivers/clk/clk-aspeed.c | 129 +++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 129 insertions(+) > > diff --git a/drivers/clk/clk-aspeed.c b/drivers/clk/clk-aspeed.c > index e614c61b82d2..19531798e040 100644 > --- a/drivers/clk/clk-aspeed.c > +++ b/drivers/clk/clk-aspeed.c > @@ -14,6 +14,8 @@ > #include <linux/clk-provider.h> > #include <linux/mfd/syscon.h> > #include <linux/of_address.h> > +#include <linux/of_device.h> > +#include <linux/platform_device.h> > #include <linux/regmap.h> > #include <linux/slab.h> > #include <linux/spinlock.h> > @@ -115,6 +117,20 @@ static const struct aspeed_gate_data aspeed_gates[] __initconst = { > /* 31: reserved */ > }; > > +static const char * const eclk_parents[] = {"d1pll", "hpll", "mpll"}; > + > +static const struct clk_div_table ast2500_mac_div_table[] = { > + { 0x0, 4 }, /* Yep, really. Aspeed confirmed this is correct */ > + { 0x1, 4 }, > + { 0x2, 6 }, > + { 0x3, 8 }, > + { 0x4, 10 }, > + { 0x5, 12 }, > + { 0x6, 14 }, > + { 0x7, 16 }, > + { 0 } > +}; > + > static const struct clk_div_table ast2400_div_table[] = { > { 0x0, 2 }, > { 0x1, 4 }, > @@ -139,6 +155,21 @@ static const struct clk_div_table ast2500_div_table[] = { > { 0 } > }; > > +struct aspeed_clk_soc_data { > + const struct clk_div_table *div_table; > + const struct clk_div_table *mac_div_table; > +}; > + > +static const struct aspeed_clk_soc_data ast2500_data = { > + .div_table = ast2500_div_table, > + .mac_div_table = ast2500_mac_div_table, > +}; > + > +static const struct aspeed_clk_soc_data ast2400_data = { > + .div_table = ast2400_div_table, > + .mac_div_table = ast2400_div_table, > +}; > + > static struct clk_hw *aspeed_calc_pll(const char *name, u32 val) > { > unsigned int mult, div; > @@ -160,6 +191,104 @@ static struct clk_hw *aspeed_calc_pll(const char *name, u32 val) > mult, div); > } > > +static int __init aspeed_clk_probe(struct platform_device *pdev) > +{ > + const struct aspeed_clk_soc_data *soc_data; > + const struct clk_div_table *mac_div_table; > + const struct clk_div_table *div_table; > + struct device *dev = &pdev->dev; > + struct regmap *map; > + struct clk_hw *hw; > + u32 val, rate; > + > + map = syscon_node_to_regmap(dev->of_node); > + if (IS_ERR(map)) { > + dev_err(dev, "no syscon regmap\n"); > + return PTR_ERR(map); > + } > + > + /* SoC generations share common layouts but have different divisors */ > + soc_data = of_device_get_match_data(&pdev->dev); > + div_table = soc_data->div_table; > + mac_div_table = soc_data->mac_div_table; > + > + /* UART clock div13 setting */ > + regmap_read(map, ASPEED_MISC_CTRL, &val); > + if (val & BIT(12)) > + rate = 24000000 / 13; > + else > + rate = 24000000; > + /* TODO: Find the parent data for the uart clock */ > + hw = clk_hw_register_fixed_rate(NULL, "uart", NULL, 0, rate); > + aspeed_clk_data->hws[ASPEED_CLK_UART] = hw; > + > + /* > + * Memory controller (M-PLL) PLL. This clock is configured by the > + * bootloader, and is exposed to Linux as a read-only clock rate. > + */ > + regmap_read(map, ASPEED_MPLL_PARAM, &val); > + aspeed_clk_data->hws[ASPEED_CLK_MPLL] = aspeed_calc_pll("mpll", val);
IIRC the calculation in aspeed_calc_pll() is appropriate for the AST2500, but not the AST2400.
> + > + /* SD/SDIO clock divider (TODO: There's a gate too) */ > + hw = clk_hw_register_divider_table(NULL, "sdio", "hpll", 0, > + scu_base + ASPEED_CLK_SELECTION, 12, 3, 0, > + div_table, > + &aspeed_clk_lock); > + aspeed_clk_data->hws[ASPEED_CLK_SDIO] = hw; > + > + /* MAC AHB bus clock divider */ > + hw = clk_hw_register_divider_table(NULL, "mac", "hpll", 0, > + scu_base + ASPEED_CLK_SELECTION, 16, 3, 0, > + mac_div_table, > + &aspeed_clk_lock); > + aspeed_clk_data->hws[ASPEED_CLK_MAC] = hw; > + > + /* LPC Host (LHCLK) clock divider */ > + hw = clk_hw_register_divider_table(NULL, "lhclk", "hpll", 0, > + scu_base + ASPEED_CLK_SELECTION, 20, 3, 0, > + div_table, > + &aspeed_clk_lock); > + aspeed_clk_data->hws[ASPEED_CLK_LHCLK] = hw; > + > + /* Video Engine (ECLK) mux and clock divider */ > + hw = clk_hw_register_mux(NULL, "eclk_mux", > + eclk_parents, ARRAY_SIZE(eclk_parents), 0, > + scu_base + ASPEED_CLK_SELECTION, 2, 2, > + 0, &aspeed_clk_lock); > + aspeed_clk_data->hws[ASPEED_CLK_ECLK_MUX] = hw; > + hw = clk_hw_register_divider_table(NULL, "eclk", "eclk_mux", 0, > + scu_base + ASPEED_CLK_SELECTION, 20, 3, 0,
On the AST2500 it looks like this should start at bit 28 for 3 bits, not bit 20. Separately, I'm not sure how to interpret the AST2400 datasheet here - maybe it's similar but with different wording ("clock slow down" rather than "divisor"?).
> + div_table,
This doesn't seem to be correct. There's the problem of 0b000 and 0b001 mapping the same value of 2 for the AST2500, whose table then increments in steps of 1. The AST2400 mapping on the otherhand is multiples of 2 starting at 2, with no inconsistency for 0b000 vs 0b001.
> + &aspeed_clk_lock); > + aspeed_clk_data->hws[ASPEED_CLK_ECLK] = hw; > + > + /* P-Bus (BCLK) clock divider */ > + hw = clk_hw_register_divider_table(NULL, "bclk", "hpll", 0, > + scu_base + ASPEED_CLK_SELECTION, 0, 2, 0,
Bit 0 in SCU08 is a 1-bit field "CPU/AHB clock dynamic slow down enable". BCLK is actually in SCU*D*8, but (perhaps confusingly) documented immediately below SCU*0*8.
Cheers,
Andrew
> + div_table, > + &aspeed_clk_lock); > + aspeed_clk_data->hws[ASPEED_CLK_BCLK] = hw; > + > + return 0; > +}; > + > +static const struct of_device_id aspeed_clk_dt_ids[] = { > + { .compatible = "aspeed,ast2400-scu", .data = &ast2400_data }, > + { .compatible = "aspeed,ast2500-scu", .data = &ast2500_data }, > + { }, > +}; > + > +static struct platform_driver aspeed_clk_driver = { > + .probe = aspeed_clk_probe, > + .driver = { > + .name = "aspeed-clk", > + .of_match_table = aspeed_clk_dt_ids, > + .suppress_bind_attrs = true, > + }, > +}; > +builtin_platform_driver(aspeed_clk_driver); > + > + > static void __init aspeed_ast2400_cc(struct regmap *map) > { > struct clk_hw *hw;[unhandled content-type:application/pgp-signature] | |