diff options
| author | Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahmanian@intel.com> | 2025-05-28 12:15:56 +0530 |
|---|---|---|
| committer | Joonas Lahtinen <joonas.lahtinen@linux.intel.com> | 2025-06-04 17:30:53 +0300 |
| commit | 791d76005de0ab556b590473eb4cbfede727fce0 (patch) | |
| tree | 71cd0d88b611ff84ed697b43ef059d69e2b5c823 | |
| parent | 0323a5127e7c534cfc88efe0f850a0cb777e938b (diff) | |
drm/i915/display: Fix u32 overflow in SNPS PHY HDMI PLL setup
When configuring the HDMI PLL, calculations use DIV_ROUND_UP_ULL and
DIV_ROUND_DOWN_ULL macros, which internally rely on do_div. However, do_div
expects a 32-bit (u32) divisor, and at higher data rates, the divisor can
exceed this limit. This leads to incorrect division results and
ultimately misconfigured PLL values.
This fix replaces do_div calls with div64_base64 calls where diviser
can exceed u32 limit.
Fixes: 5947642004bf ("drm/i915/display: Add support for SNPS PHY HDMI PLL algorithm for DG2")
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Cc: Suraj Kandpal <suraj.kandpal@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahmanian@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://lore.kernel.org/r/20250528064557.4172149-1-dibin.moolakadan.subrahmanian@intel.com
(cherry picked from commit ce924116e43ffbfa544d82976c4b9d11bcde9334)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_snps_hdmi_pll.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_snps_hdmi_pll.c b/drivers/gpu/drm/i915/display/intel_snps_hdmi_pll.c index c6321dafef4f..74bb3bedf30f 100644 --- a/drivers/gpu/drm/i915/display/intel_snps_hdmi_pll.c +++ b/drivers/gpu/drm/i915/display/intel_snps_hdmi_pll.c @@ -41,12 +41,12 @@ static s64 interp(s64 x, s64 x1, s64 x2, s64 y1, s64 y2) { s64 dydx; - dydx = DIV_ROUND_UP_ULL((y2 - y1) * 100000, (x2 - x1)); + dydx = DIV64_U64_ROUND_UP((y2 - y1) * 100000, (x2 - x1)); - return (y1 + DIV_ROUND_UP_ULL(dydx * (x - x1), 100000)); + return (y1 + DIV64_U64_ROUND_UP(dydx * (x - x1), 100000)); } -static void get_ana_cp_int_prop(u32 vco_clk, +static void get_ana_cp_int_prop(u64 vco_clk, u32 refclk_postscalar, int mpll_ana_v2i, int c, int a, @@ -115,16 +115,16 @@ static void get_ana_cp_int_prop(u32 vco_clk, CURVE0_MULTIPLIER)); scaled_interpolated_sqrt = - int_sqrt(DIV_ROUND_UP_ULL(interpolated_product, vco_div_refclk_float) * + int_sqrt(DIV64_U64_ROUND_UP(interpolated_product, vco_div_refclk_float) * DIV_ROUND_DOWN_ULL(1000000000000ULL, 55)); /* Scale vco_div_refclk for ana_cp_int */ scaled_vco_div_refclk2 = DIV_ROUND_UP_ULL(vco_div_refclk_float, 1000000); - adjusted_vco_clk2 = 1460281 * DIV_ROUND_UP_ULL(scaled_interpolated_sqrt * + adjusted_vco_clk2 = 1460281 * DIV64_U64_ROUND_UP(scaled_interpolated_sqrt * scaled_vco_div_refclk2, curve_1_interpolated); - *ana_cp_prop = DIV_ROUND_UP_ULL(adjusted_vco_clk2, curve_2_scaled2); + *ana_cp_prop = DIV64_U64_ROUND_UP(adjusted_vco_clk2, curve_2_scaled2); *ana_cp_prop = max(1, min(*ana_cp_prop, 127)); } @@ -165,10 +165,10 @@ static void compute_hdmi_tmds_pll(u64 pixel_clock, u32 refclk, /* Select appropriate v2i point */ if (datarate <= INTEL_SNPS_PHY_HDMI_9999MHZ) { mpll_ana_v2i = 2; - tx_clk_div = ilog2(DIV_ROUND_DOWN_ULL(INTEL_SNPS_PHY_HDMI_9999MHZ, datarate)); + tx_clk_div = ilog2(div64_u64(INTEL_SNPS_PHY_HDMI_9999MHZ, datarate)); } else { mpll_ana_v2i = 3; - tx_clk_div = ilog2(DIV_ROUND_DOWN_ULL(INTEL_SNPS_PHY_HDMI_16GHZ, datarate)); + tx_clk_div = ilog2(div64_u64(INTEL_SNPS_PHY_HDMI_16GHZ, datarate)); } vco_clk = (datarate << tx_clk_div) >> 1; |