From: Conor Dooley conor.dooley@microchip.com
[ Upstream commit 14016e4aafc5f157c10fb1a386fa3b3bd9c30e9a ]
The MSS pll is not a fixed frequency clock, so add set() & round_rate() support. Control is limited to a 7 bit output divider as other devices on the FPGA occupy the other three outputs of the PLL & prevent changing the multiplier.
Reviewed-by: Daire McNamara daire.mcnamara@microchip.com Signed-off-by: Conor Dooley conor.dooley@microchip.com Reviewed-by: Claudiu Beznea claudiu.beznea@microchip.com Signed-off-by: Claudiu Beznea claudiu.beznea@microchip.com Link: https://lore.kernel.org/r/20220909123123.2699583-9-conor.dooley@microchip.co... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/clk/microchip/clk-mpfs.c | 54 ++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+)
diff --git a/drivers/clk/microchip/clk-mpfs.c b/drivers/clk/microchip/clk-mpfs.c index b6b89413e090..cb4ec4749279 100644 --- a/drivers/clk/microchip/clk-mpfs.c +++ b/drivers/clk/microchip/clk-mpfs.c @@ -126,8 +126,62 @@ static unsigned long mpfs_clk_msspll_recalc_rate(struct clk_hw *hw, unsigned lon return prate * mult / (ref_div * MSSPLL_FIXED_DIV * postdiv); }
+static long mpfs_clk_msspll_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate) +{ + struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw); + void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset; + void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR; + u32 mult, ref_div; + unsigned long rate_before_ctrl; + + mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT; + mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH); + ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT; + ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH); + + rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult; + + return divider_round_rate(hw, rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH, + msspll_hw->flags); +} + +static int mpfs_clk_msspll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate) +{ + struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw); + void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset; + void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR; + void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR; + u32 mult, ref_div, postdiv; + int divider_setting; + unsigned long rate_before_ctrl, flags; + + mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT; + mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH); + ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT; + ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH); + + rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult; + divider_setting = divider_get_val(rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH, + msspll_hw->flags); + + if (divider_setting < 0) + return divider_setting; + + spin_lock_irqsave(&mpfs_clk_lock, flags); + + postdiv = readl_relaxed(postdiv_addr); + postdiv &= ~(clk_div_mask(MSSPLL_POSTDIV_WIDTH) << MSSPLL_POSTDIV_SHIFT); + writel_relaxed(postdiv, postdiv_addr); + + spin_unlock_irqrestore(&mpfs_clk_lock, flags); + + return 0; +} + static const struct clk_ops mpfs_clk_msspll_ops = { .recalc_rate = mpfs_clk_msspll_recalc_rate, + .round_rate = mpfs_clk_msspll_round_rate, + .set_rate = mpfs_clk_msspll_set_rate, };
#define CLK_PLL(_id, _name, _parent, _shift, _width, _flags, _offset) { \