From b98e2113b53fa9c7474a820bcd94fffb352acdf6 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Fri, 3 Feb 2023 14:23:38 +0000 Subject: ArmPkg/ArmScmiDxe: Fix the calculation of RequiredArraySize As per the SCMI specification, section CLOCK_DESCRIBE_RATES mentions that the value of num_rates_flags[11:0] in the response must be 3 if the return format is the triplet. Due to the buggy firmware, this was not noticed for long time. The firmware is now fixed resulting in ClockDescribeRates() to fail with "Buffer Too Small" error as the RequiredArraySize gets miscalculated as 72 instead of 24. Fix the issue by reusing the logic for both the return format which must work if num_rates_flags has correct value as expected from the specification. Cc: Girish Pathak Cc: Jeff Brasen Reviewed-by: Pierre Gondois Tested-by: Pierre Gondois Reported-by: Sami Mujawar Signed-off-by: Sudeep Holla Reviewed-by: Sami Mujawar Tested-by: Sami Mujawar --- ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c | 39 +++++++++++---------------- 1 file changed, 16 insertions(+), 23 deletions(-) diff --git a/ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c b/ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c index 12a7e6df5d..f092208a66 100644 --- a/ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c +++ b/ArmPkg/Drivers/ArmScmiDxe/ScmiClockProtocol.c @@ -236,12 +236,7 @@ ClockDescribeRates ( *TotalRates = NUM_RATES (DescribeRates->NumRatesFlags) + NUM_REMAIN_RATES (DescribeRates->NumRatesFlags); - if (*Format == ScmiClockRateFormatDiscrete) { - RequiredArraySize = (*TotalRates) * sizeof (UINT64); - } else { - // We need to return triplet of 64 bit value for each rate - RequiredArraySize = (*TotalRates) * 3 * sizeof (UINT64); - } + RequiredArraySize = (*TotalRates) * sizeof (UINT64); if (RequiredArraySize > (*RateArraySize)) { *RateArraySize = RequiredArraySize; @@ -259,23 +254,21 @@ ClockDescribeRates ( ConvertTo64Bit (Rate->Low, Rate->High); } } else { - for (RateNo = 0; RateNo < NUM_RATES (DescribeRates->NumRatesFlags); RateNo++) { - // Linear clock rates from minimum to maximum in steps - // Minimum clock rate. - Rate = &DescribeRates->Rates[RateOffset++]; - RateArray[RateIndex].ContinuousRate.Min = - ConvertTo64Bit (Rate->Low, Rate->High); - - Rate = &DescribeRates->Rates[RateOffset++]; - // Maximum clock rate. - RateArray[RateIndex].ContinuousRate.Max = - ConvertTo64Bit (Rate->Low, Rate->High); - - Rate = &DescribeRates->Rates[RateOffset++]; - // Step. - RateArray[RateIndex++].ContinuousRate.Step = - ConvertTo64Bit (Rate->Low, Rate->High); - } + // Linear clock rates from minimum to maximum in steps + // Minimum clock rate. + Rate = &DescribeRates->Rates[RateOffset++]; + RateArray[RateIndex].ContinuousRate.Min = + ConvertTo64Bit (Rate->Low, Rate->High); + + Rate = &DescribeRates->Rates[RateOffset++]; + // Maximum clock rate. + RateArray[RateIndex].ContinuousRate.Max = + ConvertTo64Bit (Rate->Low, Rate->High); + + Rate = &DescribeRates->Rates[RateOffset++]; + // Step. + RateArray[RateIndex++].ContinuousRate.Step = + ConvertTo64Bit (Rate->Low, Rate->High); } } while (NUM_REMAIN_RATES (DescribeRates->NumRatesFlags) != 0); -- cgit v1.2.3