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author | Sam Protsenko <semen.protsenko@linaro.org> | 2021-10-08 18:43:48 +0300 |
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committer | Sylwester Nawrocki <s.nawrocki@samsung.com> | 2021-10-09 22:19:58 +0200 |
commit | 8f90f43a095d99144219fd3a5d1d5ddfb250b808 (patch) | |
tree | 98e6d5db1ddd6f2ce31128997f5f0c2eac7ff2d2 /drivers | |
parent | 1d26eaeec37a91ff4575f6fead889818c5895304 (diff) | |
download | linux-stable-8f90f43a095d99144219fd3a5d1d5ddfb250b808.tar.gz linux-stable-8f90f43a095d99144219fd3a5d1d5ddfb250b808.tar.bz2 linux-stable-8f90f43a095d99144219fd3a5d1d5ddfb250b808.zip |
clk: samsung: clk-pll: Implement pll0822x PLL type
pll0822x PLL is used in Exynos850 SoC for top-level integer PLLs. The
code was derived from very similar pll35xx type, with next differences:
1. Lock time for pll0822x is 150*P_DIV, when for pll35xx it's 270*P_DIV
2. It's not suggested in Exynos850 TRM that S_DIV change doesn't require
performing PLL lock procedure (which is done in pll35xx
implementation)
When defining pll0822x type, CON3 register offset should be provided as
a "con" parameter of PLL() macro, like this:
PLL(pll_0822x, 0, "fout_shared0_pll", "oscclk",
PLL_LOCKTIME_PLL_SHARED0, PLL_CON3_PLL_SHARED0,
exynos850_shared0_pll_rates),
To define PLL rates table, one can use PLL_35XX_RATE() macro, e.g.:
PLL_35XX_RATE(26 * MHZ, 1600 * MHZ, 800, 13, 0)
as it's completely appropriate for pl0822x type and there is no sense in
duplicating that.
If bit #1 (MANUAL_PLL_CTRL) is not set in CON1 register, it won't be
possible to set new rate, with next error showing in kernel log:
Could not lock PLL fout_shared1_pll
That can happen for example if bootloader clears that bit beforehand.
PLL driver doesn't account for that, so if MANUAL_PLL_CTRL bit was
cleared, it's assumed it was done for a reason and it shouldn't be
possible to change that PLL's rate at all.
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Link: https://lore.kernel.org/r/20211008154352.19519-2-semen.protsenko@linaro.org
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/clk/samsung/clk-pll.c | 91 | ||||
-rw-r--r-- | drivers/clk/samsung/clk-pll.h | 1 |
2 files changed, 92 insertions, 0 deletions
diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c index 5873a9354b50..03131b149c0b 100644 --- a/drivers/clk/samsung/clk-pll.c +++ b/drivers/clk/samsung/clk-pll.c @@ -416,6 +416,89 @@ static const struct clk_ops samsung_pll36xx_clk_min_ops = { }; /* + * PLL0822x Clock Type + */ +/* Maximum lock time can be 150 * PDIV cycles */ +#define PLL0822X_LOCK_FACTOR (150) + +#define PLL0822X_MDIV_MASK (0x3FF) +#define PLL0822X_PDIV_MASK (0x3F) +#define PLL0822X_SDIV_MASK (0x7) +#define PLL0822X_MDIV_SHIFT (16) +#define PLL0822X_PDIV_SHIFT (8) +#define PLL0822X_SDIV_SHIFT (0) +#define PLL0822X_LOCK_STAT_SHIFT (29) +#define PLL0822X_ENABLE_SHIFT (31) + +static unsigned long samsung_pll0822x_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct samsung_clk_pll *pll = to_clk_pll(hw); + u32 mdiv, pdiv, sdiv, pll_con3; + u64 fvco = parent_rate; + + pll_con3 = readl_relaxed(pll->con_reg); + mdiv = (pll_con3 >> PLL0822X_MDIV_SHIFT) & PLL0822X_MDIV_MASK; + pdiv = (pll_con3 >> PLL0822X_PDIV_SHIFT) & PLL0822X_PDIV_MASK; + sdiv = (pll_con3 >> PLL0822X_SDIV_SHIFT) & PLL0822X_SDIV_MASK; + + fvco *= mdiv; + do_div(fvco, (pdiv << sdiv)); + + return (unsigned long)fvco; +} + +static int samsung_pll0822x_set_rate(struct clk_hw *hw, unsigned long drate, + unsigned long prate) +{ + const struct samsung_pll_rate_table *rate; + struct samsung_clk_pll *pll = to_clk_pll(hw); + u32 pll_con3; + + /* Get required rate settings from table */ + rate = samsung_get_pll_settings(pll, drate); + if (!rate) { + pr_err("%s: Invalid rate : %lu for pll clk %s\n", __func__, + drate, clk_hw_get_name(hw)); + return -EINVAL; + } + + /* Change PLL PMS values */ + pll_con3 = readl_relaxed(pll->con_reg); + pll_con3 &= ~((PLL0822X_MDIV_MASK << PLL0822X_MDIV_SHIFT) | + (PLL0822X_PDIV_MASK << PLL0822X_PDIV_SHIFT) | + (PLL0822X_SDIV_MASK << PLL0822X_SDIV_SHIFT)); + pll_con3 |= (rate->mdiv << PLL0822X_MDIV_SHIFT) | + (rate->pdiv << PLL0822X_PDIV_SHIFT) | + (rate->sdiv << PLL0822X_SDIV_SHIFT); + + /* Set PLL lock time */ + writel_relaxed(rate->pdiv * PLL0822X_LOCK_FACTOR, + pll->lock_reg); + + /* Write PMS values */ + writel_relaxed(pll_con3, pll->con_reg); + + /* Wait for PLL lock if the PLL is enabled */ + if (pll_con3 & BIT(pll->enable_offs)) + return samsung_pll_lock_wait(pll, BIT(pll->lock_offs)); + + return 0; +} + +static const struct clk_ops samsung_pll0822x_clk_ops = { + .recalc_rate = samsung_pll0822x_recalc_rate, + .round_rate = samsung_pll_round_rate, + .set_rate = samsung_pll0822x_set_rate, + .enable = samsung_pll3xxx_enable, + .disable = samsung_pll3xxx_disable, +}; + +static const struct clk_ops samsung_pll0822x_clk_min_ops = { + .recalc_rate = samsung_pll0822x_recalc_rate, +}; + +/* * PLL45xx Clock Type */ #define PLL4502_LOCK_FACTOR 400 @@ -1296,6 +1379,14 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx, else init.ops = &samsung_pll35xx_clk_ops; break; + case pll_0822x: + pll->enable_offs = PLL0822X_ENABLE_SHIFT; + pll->lock_offs = PLL0822X_LOCK_STAT_SHIFT; + if (!pll->rate_table) + init.ops = &samsung_pll0822x_clk_min_ops; + else + init.ops = &samsung_pll0822x_clk_ops; + break; case pll_4500: init.ops = &samsung_pll45xx_clk_min_ops; break; diff --git a/drivers/clk/samsung/clk-pll.h b/drivers/clk/samsung/clk-pll.h index 79e41c226b90..213e94a97f23 100644 --- a/drivers/clk/samsung/clk-pll.h +++ b/drivers/clk/samsung/clk-pll.h @@ -36,6 +36,7 @@ enum samsung_pll_type { pll_1451x, pll_1452x, pll_1460x, + pll_0822x, }; #define PLL_RATE(_fin, _m, _p, _s, _k, _ks) \ |