5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jay Buddhabhatti jay.buddhabhatti@amd.com
[ Upstream commit 1fe15be1fb613534ecbac5f8c3f8744f757d237d ]
Currently zynqmp divider round rate is considering single parent and calculating rate and parent rate accordingly. But if divider clock flag is set to SET_RATE_PARENT then its not trying to traverse through all parent rate and not selecting best parent rate from that. So use common divider_round_rate() which is traversing through all clock parents and its rate and calculating proper parent rate.
Fixes: 3fde0e16d016 ("drivers: clk: Add ZynqMP clock driver") Signed-off-by: Jay Buddhabhatti jay.buddhabhatti@amd.com Link: https://lore.kernel.org/r/20231129112916.23125-3-jay.buddhabhatti@amd.com Signed-off-by: Stephen Boyd sboyd@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/clk/zynqmp/divider.c | 66 +++--------------------------------- 1 file changed, 5 insertions(+), 61 deletions(-)
diff --git a/drivers/clk/zynqmp/divider.c b/drivers/clk/zynqmp/divider.c index 47a199346ddf..e25c76ff2739 100644 --- a/drivers/clk/zynqmp/divider.c +++ b/drivers/clk/zynqmp/divider.c @@ -110,52 +110,6 @@ static unsigned long zynqmp_clk_divider_recalc_rate(struct clk_hw *hw, return DIV_ROUND_UP_ULL(parent_rate, value); }
-static void zynqmp_get_divider2_val(struct clk_hw *hw, - unsigned long rate, - struct zynqmp_clk_divider *divider, - u32 *bestdiv) -{ - int div1; - int div2; - long error = LONG_MAX; - unsigned long div1_prate; - struct clk_hw *div1_parent_hw; - struct zynqmp_clk_divider *pdivider; - struct clk_hw *div2_parent_hw = clk_hw_get_parent(hw); - - if (!div2_parent_hw) - return; - - pdivider = to_zynqmp_clk_divider(div2_parent_hw); - if (!pdivider) - return; - - div1_parent_hw = clk_hw_get_parent(div2_parent_hw); - if (!div1_parent_hw) - return; - - div1_prate = clk_hw_get_rate(div1_parent_hw); - *bestdiv = 1; - for (div1 = 1; div1 <= pdivider->max_div;) { - for (div2 = 1; div2 <= divider->max_div;) { - long new_error = ((div1_prate / div1) / div2) - rate; - - if (abs(new_error) < abs(error)) { - *bestdiv = div2; - error = new_error; - } - if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) - div2 = div2 << 1; - else - div2++; - } - if (pdivider->flags & CLK_DIVIDER_POWER_OF_TWO) - div1 = div1 << 1; - else - div1++; - } -} - /** * zynqmp_clk_divider_round_rate() - Round rate of divider clock * @hw: handle between common and hardware-specific interfaces @@ -174,6 +128,7 @@ static long zynqmp_clk_divider_round_rate(struct clk_hw *hw, u32 div_type = divider->div_type; u32 bestdiv; int ret; + u8 width;
/* if read only, just return current value */ if (divider->flags & CLK_DIVIDER_READ_ONLY) { @@ -193,23 +148,12 @@ static long zynqmp_clk_divider_round_rate(struct clk_hw *hw, return DIV_ROUND_UP_ULL((u64)*prate, bestdiv); }
- bestdiv = zynqmp_divider_get_val(*prate, rate, divider->flags); - - /* - * In case of two divisors, compute best divider values and return - * divider2 value based on compute value. div1 will be automatically - * set to optimum based on required total divider value. - */ - if (div_type == TYPE_DIV2 && - (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) { - zynqmp_get_divider2_val(hw, rate, divider, &bestdiv); - } + width = fls(divider->max_div);
- if ((clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) && divider->is_frac) - bestdiv = rate % *prate ? 1 : bestdiv; + rate = divider_round_rate(hw, rate, prate, NULL, width, divider->flags);
- bestdiv = min_t(u32, bestdiv, divider->max_div); - *prate = rate * bestdiv; + if (divider->is_frac && (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) && (rate % *prate)) + *prate = rate;
return rate; }