Re: [PATCH v2 6/7] clk: samsung: clk-pll: Add support for pll_1418x
From: Krzysztof Kozlowski <krzk@kernel.org>
Date: 2024-08-08 09:39:28
Also in:
linux-clk, linux-devicetree, linux-samsung-soc, lkml
On 06/08/2024 14:11, David Virag wrote:
quoted hunk ↗ jump to hunk
pll1418x is used in Exynos7885 SoC for USB PHY clock. Operation-wise it is very similar to pll0822x, except that MDIV is only 9 bits wide instead of 10, and we use the CON1 register in the PLL macro's "con" parameter instead of CON3 like this: PLL(pll_1418x, CLK_FOUT_USB_PLL, "fout_usb_pll", "oscclk", PLL_LOCKTIME_PLL_USB, PLL_CON0_PLL_USB, pll_usb_rate_table), Technically the PLL should work fine with pll0822x code if the PLL tables are correct, but it's more "correct" to actually update the mask. Signed-off-by: David Virag <redacted> --- drivers/clk/samsung/clk-pll.c | 20 ++++++++++++++++---- drivers/clk/samsung/clk-pll.h | 1 + 2 files changed, 17 insertions(+), 4 deletions(-)diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c index 4be879ab917e..c61a2810737c 100644 --- a/drivers/clk/samsung/clk-pll.c +++ b/drivers/clk/samsung/clk-pll.c@@ -430,6 +430,9 @@ static const struct clk_ops samsung_pll36xx_clk_min_ops = { #define PLL0822X_LOCK_STAT_SHIFT (29) #define PLL0822X_ENABLE_SHIFT (31) +/* PLL1418x is similar to PLL0822x, except that MDIV is one bit smaller */ +#define PLL1418X_MDIV_MASK (0x1FF) + static unsigned long samsung_pll0822x_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) {@@ -438,7 +441,10 @@ static unsigned long samsung_pll0822x_recalc_rate(struct clk_hw *hw, u64 fvco = parent_rate; pll_con3 = readl_relaxed(pll->con_reg); - mdiv = (pll_con3 >> PLL0822X_MDIV_SHIFT) & PLL0822X_MDIV_MASK; + if (pll->type != pll_1418x) + mdiv = (pll_con3 >> PLL0822X_MDIV_SHIFT) & PLL0822X_MDIV_MASK; + else + mdiv = (pll_con3 >> PLL0822X_MDIV_SHIFT) & PLL1418X_MDIV_MASK; pdiv = (pll_con3 >> PLL0822X_PDIV_SHIFT) & PLL0822X_PDIV_MASK; sdiv = (pll_con3 >> PLL0822X_SDIV_SHIFT) & PLL0822X_SDIV_MASK;@@ -468,9 +474,14 @@ static int samsung_pll0822x_set_rate(struct clk_hw *hw, unsigned long drate, /* 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)); + if (pll->type != pll_1418x) + pll_con3 &= ~((PLL0822X_MDIV_MASK << PLL0822X_MDIV_SHIFT) | + (PLL0822X_PDIV_MASK << PLL0822X_PDIV_SHIFT) | + (PLL0822X_SDIV_MASK << PLL0822X_SDIV_SHIFT));
I think this part could be simpler. If I read it correctly, only mdiv mask is different, so create local variable mdiv_mask and set it in if-else block accordingly to the type. Then here you have non-conditional code: pll_con3 &= ~((mdiv_mask << PLL0822X_MDIV_SHIFT) | Best regards, Krzysztof