[PATCH] drm/radeon/ni_dpm: Fix booting bug

Alex Deucher alexdeucher at gmail.com
Mon May 10 21:17:17 UTC 2021


On Sun, May 9, 2021 at 6:48 PM Gustavo A. R. Silva
<gustavoars at kernel.org> wrote:
>
> Create new structure NISLANDS_SMC_SWSTATE_SINGLE, as initialState.levels
> and ACPIState.levels are never actually used as flexible arrays. Those
> arrays can be used as simple objects of type
> NISLANDS_SMC_HW_PERFORMANCE_LEVEL, instead.
>
> Currently, the code fails because flexible array _levels_ in
> struct NISLANDS_SMC_SWSTATE doesn't allow for code that access
> the first element of initialState.levels and ACPIState.levels
> arrays:
>
> drivers/gpu/drm/radeon/ni_dpm.c:
> 1690         table->initialState.levels[0].mclk.vMPLL_AD_FUNC_CNTL =
> 1691                 cpu_to_be32(ni_pi->clock_registers.mpll_ad_func_cntl);
> ...
> 1903:   table->ACPIState.levels[0].mclk.vMPLL_AD_FUNC_CNTL = cpu_to_be32(mpll_ad_func_cntl);
> 1904:   table->ACPIState.levels[0].mclk.vMPLL_AD_FUNC_CNTL_2 = cpu_to_be32(mpll_ad_func_cntl_2);
>
> because such element cannot exist without previously allocating
> any dynamic memory for it (which never actually happens).
>
> That's why struct NISLANDS_SMC_SWSTATE should only be used as type
> for object driverState and new struct SISLANDS_SMC_SWSTATE_SINGLE is
> created as type for objects initialState, ACPIState and ULVState.
>
> Also, with the change from one-element array to flexible-array member
> in commit 434fb1e7444a ("drm/radeon/nislands_smc.h: Replace one-element
> array with flexible-array member in struct NISLANDS_SMC_SWSTATE"), the
> size of dpmLevels in struct NISLANDS_SMC_STATETABLE should be fixed to
> be NISLANDS_MAX_SMC_PERFORMANCE_LEVELS_PER_SWSTATE instead of
> NISLANDS_MAX_SMC_PERFORMANCE_LEVELS_PER_SWSTATE - 1.
>
> Bug: https://lore.kernel.org/dri-devel/3eedbe78-1fbd-4763-a7f3-ac5665e76a4a@xenosoft.de/
> Fixes: 434fb1e7444a ("drm/radeon/nislands_smc.h: Replace one-element array with flexible-array member in struct NISLANDS_SMC_SWSTATE")
> Cc: stable at vger.kernel.org
> Reported-by: Christian Zigotzky <chzigotzky at xenosoft.de>
> Tested-by: Christian Zigotzky <chzigotzky at xenosoft.de>
> Link: https://lore.kernel.org/dri-devel/9bb5fcbd-daf5-1669-b3e7-b8624b3c36f9@xenosoft.de/
> Signed-off-by: Gustavo A. R. Silva <gustavoars at kernel.org>

This seems like a lot of churn just to use flexible arrays.  That
said, if static checkers are going to keep complaining about single
element arrays, I don't mind applying these patches since this code is
not likely to change.  Applied.  Thanks.

Alex


Alex

> ---
>  drivers/gpu/drm/radeon/ni_dpm.c       | 144 +++++++++++++-------------
>  drivers/gpu/drm/radeon/nislands_smc.h |  34 +++---
>  2 files changed, 94 insertions(+), 84 deletions(-)
>
> diff --git a/drivers/gpu/drm/radeon/ni_dpm.c b/drivers/gpu/drm/radeon/ni_dpm.c
> index dd5ef6493723..769f666335ac 100644
> --- a/drivers/gpu/drm/radeon/ni_dpm.c
> +++ b/drivers/gpu/drm/radeon/ni_dpm.c
> @@ -1687,102 +1687,102 @@ static int ni_populate_smc_initial_state(struct radeon_device *rdev,
>         u32 reg;
>         int ret;
>
> -       table->initialState.levels[0].mclk.vMPLL_AD_FUNC_CNTL =
> +       table->initialState.level.mclk.vMPLL_AD_FUNC_CNTL =
>                 cpu_to_be32(ni_pi->clock_registers.mpll_ad_func_cntl);
> -       table->initialState.levels[0].mclk.vMPLL_AD_FUNC_CNTL_2 =
> +       table->initialState.level.mclk.vMPLL_AD_FUNC_CNTL_2 =
>                 cpu_to_be32(ni_pi->clock_registers.mpll_ad_func_cntl_2);
> -       table->initialState.levels[0].mclk.vMPLL_DQ_FUNC_CNTL =
> +       table->initialState.level.mclk.vMPLL_DQ_FUNC_CNTL =
>                 cpu_to_be32(ni_pi->clock_registers.mpll_dq_func_cntl);
> -       table->initialState.levels[0].mclk.vMPLL_DQ_FUNC_CNTL_2 =
> +       table->initialState.level.mclk.vMPLL_DQ_FUNC_CNTL_2 =
>                 cpu_to_be32(ni_pi->clock_registers.mpll_dq_func_cntl_2);
> -       table->initialState.levels[0].mclk.vMCLK_PWRMGT_CNTL =
> +       table->initialState.level.mclk.vMCLK_PWRMGT_CNTL =
>                 cpu_to_be32(ni_pi->clock_registers.mclk_pwrmgt_cntl);
> -       table->initialState.levels[0].mclk.vDLL_CNTL =
> +       table->initialState.level.mclk.vDLL_CNTL =
>                 cpu_to_be32(ni_pi->clock_registers.dll_cntl);
> -       table->initialState.levels[0].mclk.vMPLL_SS =
> +       table->initialState.level.mclk.vMPLL_SS =
>                 cpu_to_be32(ni_pi->clock_registers.mpll_ss1);
> -       table->initialState.levels[0].mclk.vMPLL_SS2 =
> +       table->initialState.level.mclk.vMPLL_SS2 =
>                 cpu_to_be32(ni_pi->clock_registers.mpll_ss2);
> -       table->initialState.levels[0].mclk.mclk_value =
> +       table->initialState.level.mclk.mclk_value =
>                 cpu_to_be32(initial_state->performance_levels[0].mclk);
>
> -       table->initialState.levels[0].sclk.vCG_SPLL_FUNC_CNTL =
> +       table->initialState.level.sclk.vCG_SPLL_FUNC_CNTL =
>                 cpu_to_be32(ni_pi->clock_registers.cg_spll_func_cntl);
> -       table->initialState.levels[0].sclk.vCG_SPLL_FUNC_CNTL_2 =
> +       table->initialState.level.sclk.vCG_SPLL_FUNC_CNTL_2 =
>                 cpu_to_be32(ni_pi->clock_registers.cg_spll_func_cntl_2);
> -       table->initialState.levels[0].sclk.vCG_SPLL_FUNC_CNTL_3 =
> +       table->initialState.level.sclk.vCG_SPLL_FUNC_CNTL_3 =
>                 cpu_to_be32(ni_pi->clock_registers.cg_spll_func_cntl_3);
> -       table->initialState.levels[0].sclk.vCG_SPLL_FUNC_CNTL_4 =
> +       table->initialState.level.sclk.vCG_SPLL_FUNC_CNTL_4 =
>                 cpu_to_be32(ni_pi->clock_registers.cg_spll_func_cntl_4);
> -       table->initialState.levels[0].sclk.vCG_SPLL_SPREAD_SPECTRUM =
> +       table->initialState.level.sclk.vCG_SPLL_SPREAD_SPECTRUM =
>                 cpu_to_be32(ni_pi->clock_registers.cg_spll_spread_spectrum);
> -       table->initialState.levels[0].sclk.vCG_SPLL_SPREAD_SPECTRUM_2 =
> +       table->initialState.level.sclk.vCG_SPLL_SPREAD_SPECTRUM_2 =
>                 cpu_to_be32(ni_pi->clock_registers.cg_spll_spread_spectrum_2);
> -       table->initialState.levels[0].sclk.sclk_value =
> +       table->initialState.level.sclk.sclk_value =
>                 cpu_to_be32(initial_state->performance_levels[0].sclk);
> -       table->initialState.levels[0].arbRefreshState =
> +       table->initialState.level.arbRefreshState =
>                 NISLANDS_INITIAL_STATE_ARB_INDEX;
>
> -       table->initialState.levels[0].ACIndex = 0;
> +       table->initialState.level.ACIndex = 0;
>
>         ret = ni_populate_voltage_value(rdev, &eg_pi->vddc_voltage_table,
>                                         initial_state->performance_levels[0].vddc,
> -                                       &table->initialState.levels[0].vddc);
> +                                       &table->initialState.level.vddc);
>         if (!ret) {
>                 u16 std_vddc;
>
>                 ret = ni_get_std_voltage_value(rdev,
> -                                              &table->initialState.levels[0].vddc,
> +                                              &table->initialState.level.vddc,
>                                                &std_vddc);
>                 if (!ret)
>                         ni_populate_std_voltage_value(rdev, std_vddc,
> -                                                     table->initialState.levels[0].vddc.index,
> -                                                     &table->initialState.levels[0].std_vddc);
> +                                                     table->initialState.level.vddc.index,
> +                                                     &table->initialState.level.std_vddc);
>         }
>
>         if (eg_pi->vddci_control)
>                 ni_populate_voltage_value(rdev,
>                                           &eg_pi->vddci_voltage_table,
>                                           initial_state->performance_levels[0].vddci,
> -                                         &table->initialState.levels[0].vddci);
> +                                         &table->initialState.level.vddci);
>
> -       ni_populate_initial_mvdd_value(rdev, &table->initialState.levels[0].mvdd);
> +       ni_populate_initial_mvdd_value(rdev, &table->initialState.level.mvdd);
>
>         reg = CG_R(0xffff) | CG_L(0);
> -       table->initialState.levels[0].aT = cpu_to_be32(reg);
> +       table->initialState.level.aT = cpu_to_be32(reg);
>
> -       table->initialState.levels[0].bSP = cpu_to_be32(pi->dsp);
> +       table->initialState.level.bSP = cpu_to_be32(pi->dsp);
>
>         if (pi->boot_in_gen2)
> -               table->initialState.levels[0].gen2PCIE = 1;
> +               table->initialState.level.gen2PCIE = 1;
>         else
> -               table->initialState.levels[0].gen2PCIE = 0;
> +               table->initialState.level.gen2PCIE = 0;
>
>         if (pi->mem_gddr5) {
> -               table->initialState.levels[0].strobeMode =
> +               table->initialState.level.strobeMode =
>                         cypress_get_strobe_mode_settings(rdev,
>                                                          initial_state->performance_levels[0].mclk);
>
>                 if (initial_state->performance_levels[0].mclk > pi->mclk_edc_enable_threshold)
> -                       table->initialState.levels[0].mcFlags = NISLANDS_SMC_MC_EDC_RD_FLAG | NISLANDS_SMC_MC_EDC_WR_FLAG;
> +                       table->initialState.level.mcFlags = NISLANDS_SMC_MC_EDC_RD_FLAG | NISLANDS_SMC_MC_EDC_WR_FLAG;
>                 else
> -                       table->initialState.levels[0].mcFlags =  0;
> +                       table->initialState.level.mcFlags =  0;
>         }
>
>         table->initialState.levelCount = 1;
>
>         table->initialState.flags |= PPSMC_SWSTATE_FLAG_DC;
>
> -       table->initialState.levels[0].dpm2.MaxPS = 0;
> -       table->initialState.levels[0].dpm2.NearTDPDec = 0;
> -       table->initialState.levels[0].dpm2.AboveSafeInc = 0;
> -       table->initialState.levels[0].dpm2.BelowSafeInc = 0;
> +       table->initialState.level.dpm2.MaxPS = 0;
> +       table->initialState.level.dpm2.NearTDPDec = 0;
> +       table->initialState.level.dpm2.AboveSafeInc = 0;
> +       table->initialState.level.dpm2.BelowSafeInc = 0;
>
>         reg = MIN_POWER_MASK | MAX_POWER_MASK;
> -       table->initialState.levels[0].SQPowerThrottle = cpu_to_be32(reg);
> +       table->initialState.level.SQPowerThrottle = cpu_to_be32(reg);
>
>         reg = MAX_POWER_DELTA_MASK | STI_SIZE_MASK | LTI_RATIO_MASK;
> -       table->initialState.levels[0].SQPowerThrottle_2 = cpu_to_be32(reg);
> +       table->initialState.level.SQPowerThrottle_2 = cpu_to_be32(reg);
>
>         return 0;
>  }
> @@ -1813,43 +1813,43 @@ static int ni_populate_smc_acpi_state(struct radeon_device *rdev,
>         if (pi->acpi_vddc) {
>                 ret = ni_populate_voltage_value(rdev,
>                                                 &eg_pi->vddc_voltage_table,
> -                                               pi->acpi_vddc, &table->ACPIState.levels[0].vddc);
> +                                               pi->acpi_vddc, &table->ACPIState.level.vddc);
>                 if (!ret) {
>                         u16 std_vddc;
>
>                         ret = ni_get_std_voltage_value(rdev,
> -                                                      &table->ACPIState.levels[0].vddc, &std_vddc);
> +                                                      &table->ACPIState.level.vddc, &std_vddc);
>                         if (!ret)
>                                 ni_populate_std_voltage_value(rdev, std_vddc,
> -                                                             table->ACPIState.levels[0].vddc.index,
> -                                                             &table->ACPIState.levels[0].std_vddc);
> +                                                             table->ACPIState.level.vddc.index,
> +                                                             &table->ACPIState.level.std_vddc);
>                 }
>
>                 if (pi->pcie_gen2) {
>                         if (pi->acpi_pcie_gen2)
> -                               table->ACPIState.levels[0].gen2PCIE = 1;
> +                               table->ACPIState.level.gen2PCIE = 1;
>                         else
> -                               table->ACPIState.levels[0].gen2PCIE = 0;
> +                               table->ACPIState.level.gen2PCIE = 0;
>                 } else {
> -                       table->ACPIState.levels[0].gen2PCIE = 0;
> +                       table->ACPIState.level.gen2PCIE = 0;
>                 }
>         } else {
>                 ret = ni_populate_voltage_value(rdev,
>                                                 &eg_pi->vddc_voltage_table,
>                                                 pi->min_vddc_in_table,
> -                                               &table->ACPIState.levels[0].vddc);
> +                                               &table->ACPIState.level.vddc);
>                 if (!ret) {
>                         u16 std_vddc;
>
>                         ret = ni_get_std_voltage_value(rdev,
> -                                                      &table->ACPIState.levels[0].vddc,
> +                                                      &table->ACPIState.level.vddc,
>                                                        &std_vddc);
>                         if (!ret)
>                                 ni_populate_std_voltage_value(rdev, std_vddc,
> -                                                             table->ACPIState.levels[0].vddc.index,
> -                                                             &table->ACPIState.levels[0].std_vddc);
> +                                                             table->ACPIState.level.vddc.index,
> +                                                             &table->ACPIState.level.std_vddc);
>                 }
> -               table->ACPIState.levels[0].gen2PCIE = 0;
> +               table->ACPIState.level.gen2PCIE = 0;
>         }
>
>         if (eg_pi->acpi_vddci) {
> @@ -1857,7 +1857,7 @@ static int ni_populate_smc_acpi_state(struct radeon_device *rdev,
>                         ni_populate_voltage_value(rdev,
>                                                   &eg_pi->vddci_voltage_table,
>                                                   eg_pi->acpi_vddci,
> -                                                 &table->ACPIState.levels[0].vddci);
> +                                                 &table->ACPIState.level.vddci);
>         }
>
>
> @@ -1900,37 +1900,37 @@ static int ni_populate_smc_acpi_state(struct radeon_device *rdev,
>         spll_func_cntl_2 &= ~SCLK_MUX_SEL_MASK;
>         spll_func_cntl_2 |= SCLK_MUX_SEL(4);
>
> -       table->ACPIState.levels[0].mclk.vMPLL_AD_FUNC_CNTL = cpu_to_be32(mpll_ad_func_cntl);
> -       table->ACPIState.levels[0].mclk.vMPLL_AD_FUNC_CNTL_2 = cpu_to_be32(mpll_ad_func_cntl_2);
> -       table->ACPIState.levels[0].mclk.vMPLL_DQ_FUNC_CNTL = cpu_to_be32(mpll_dq_func_cntl);
> -       table->ACPIState.levels[0].mclk.vMPLL_DQ_FUNC_CNTL_2 = cpu_to_be32(mpll_dq_func_cntl_2);
> -       table->ACPIState.levels[0].mclk.vMCLK_PWRMGT_CNTL = cpu_to_be32(mclk_pwrmgt_cntl);
> -       table->ACPIState.levels[0].mclk.vDLL_CNTL = cpu_to_be32(dll_cntl);
> +       table->ACPIState.level.mclk.vMPLL_AD_FUNC_CNTL = cpu_to_be32(mpll_ad_func_cntl);
> +       table->ACPIState.level.mclk.vMPLL_AD_FUNC_CNTL_2 = cpu_to_be32(mpll_ad_func_cntl_2);
> +       table->ACPIState.level.mclk.vMPLL_DQ_FUNC_CNTL = cpu_to_be32(mpll_dq_func_cntl);
> +       table->ACPIState.level.mclk.vMPLL_DQ_FUNC_CNTL_2 = cpu_to_be32(mpll_dq_func_cntl_2);
> +       table->ACPIState.level.mclk.vMCLK_PWRMGT_CNTL = cpu_to_be32(mclk_pwrmgt_cntl);
> +       table->ACPIState.level.mclk.vDLL_CNTL = cpu_to_be32(dll_cntl);
>
> -       table->ACPIState.levels[0].mclk.mclk_value = 0;
> +       table->ACPIState.level.mclk.mclk_value = 0;
>
> -       table->ACPIState.levels[0].sclk.vCG_SPLL_FUNC_CNTL = cpu_to_be32(spll_func_cntl);
> -       table->ACPIState.levels[0].sclk.vCG_SPLL_FUNC_CNTL_2 = cpu_to_be32(spll_func_cntl_2);
> -       table->ACPIState.levels[0].sclk.vCG_SPLL_FUNC_CNTL_3 = cpu_to_be32(spll_func_cntl_3);
> -       table->ACPIState.levels[0].sclk.vCG_SPLL_FUNC_CNTL_4 = cpu_to_be32(spll_func_cntl_4);
> +       table->ACPIState.level.sclk.vCG_SPLL_FUNC_CNTL = cpu_to_be32(spll_func_cntl);
> +       table->ACPIState.level.sclk.vCG_SPLL_FUNC_CNTL_2 = cpu_to_be32(spll_func_cntl_2);
> +       table->ACPIState.level.sclk.vCG_SPLL_FUNC_CNTL_3 = cpu_to_be32(spll_func_cntl_3);
> +       table->ACPIState.level.sclk.vCG_SPLL_FUNC_CNTL_4 = cpu_to_be32(spll_func_cntl_4);
>
> -       table->ACPIState.levels[0].sclk.sclk_value = 0;
> +       table->ACPIState.level.sclk.sclk_value = 0;
>
> -       ni_populate_mvdd_value(rdev, 0, &table->ACPIState.levels[0].mvdd);
> +       ni_populate_mvdd_value(rdev, 0, &table->ACPIState.level.mvdd);
>
>         if (eg_pi->dynamic_ac_timing)
> -               table->ACPIState.levels[0].ACIndex = 1;
> +               table->ACPIState.level.ACIndex = 1;
>
> -       table->ACPIState.levels[0].dpm2.MaxPS = 0;
> -       table->ACPIState.levels[0].dpm2.NearTDPDec = 0;
> -       table->ACPIState.levels[0].dpm2.AboveSafeInc = 0;
> -       table->ACPIState.levels[0].dpm2.BelowSafeInc = 0;
> +       table->ACPIState.level.dpm2.MaxPS = 0;
> +       table->ACPIState.level.dpm2.NearTDPDec = 0;
> +       table->ACPIState.level.dpm2.AboveSafeInc = 0;
> +       table->ACPIState.level.dpm2.BelowSafeInc = 0;
>
>         reg = MIN_POWER_MASK | MAX_POWER_MASK;
> -       table->ACPIState.levels[0].SQPowerThrottle = cpu_to_be32(reg);
> +       table->ACPIState.level.SQPowerThrottle = cpu_to_be32(reg);
>
>         reg = MAX_POWER_DELTA_MASK | STI_SIZE_MASK | LTI_RATIO_MASK;
> -       table->ACPIState.levels[0].SQPowerThrottle_2 = cpu_to_be32(reg);
> +       table->ACPIState.level.SQPowerThrottle_2 = cpu_to_be32(reg);
>
>         return 0;
>  }
> @@ -1980,7 +1980,9 @@ static int ni_init_smc_table(struct radeon_device *rdev)
>         if (ret)
>                 return ret;
>
> -       table->driverState = table->initialState;
> +       table->driverState.flags = table->initialState.flags;
> +       table->driverState.levelCount = table->initialState.levelCount;
> +       table->driverState.levels[0] = table->initialState.level;
>
>         table->ULVState = table->initialState;
>
> diff --git a/drivers/gpu/drm/radeon/nislands_smc.h b/drivers/gpu/drm/radeon/nislands_smc.h
> index 7395cb6b3cac..42f3bab0f9ee 100644
> --- a/drivers/gpu/drm/radeon/nislands_smc.h
> +++ b/drivers/gpu/drm/radeon/nislands_smc.h
> @@ -143,6 +143,14 @@ struct NISLANDS_SMC_SWSTATE
>
>  typedef struct NISLANDS_SMC_SWSTATE NISLANDS_SMC_SWSTATE;
>
> +struct NISLANDS_SMC_SWSTATE_SINGLE {
> +       uint8_t                             flags;
> +       uint8_t                             levelCount;
> +       uint8_t                             padding2;
> +       uint8_t                             padding3;
> +       NISLANDS_SMC_HW_PERFORMANCE_LEVEL   level;
> +};
> +
>  #define NISLANDS_SMC_VOLTAGEMASK_VDDC  0
>  #define NISLANDS_SMC_VOLTAGEMASK_MVDD  1
>  #define NISLANDS_SMC_VOLTAGEMASK_VDDCI 2
> @@ -160,19 +168,19 @@ typedef struct NISLANDS_SMC_VOLTAGEMASKTABLE NISLANDS_SMC_VOLTAGEMASKTABLE;
>
>  struct NISLANDS_SMC_STATETABLE
>  {
> -    uint8_t                             thermalProtectType;
> -    uint8_t                             systemFlags;
> -    uint8_t                             maxVDDCIndexInPPTable;
> -    uint8_t                             extraFlags;
> -    uint8_t                             highSMIO[NISLANDS_MAX_NO_VREG_STEPS];
> -    uint32_t                            lowSMIO[NISLANDS_MAX_NO_VREG_STEPS];
> -    NISLANDS_SMC_VOLTAGEMASKTABLE       voltageMaskTable;
> -    PP_NIslands_DPM2Parameters          dpm2Params;
> -    NISLANDS_SMC_SWSTATE                initialState;
> -    NISLANDS_SMC_SWSTATE                ACPIState;
> -    NISLANDS_SMC_SWSTATE                ULVState;
> -    NISLANDS_SMC_SWSTATE                driverState;
> -    NISLANDS_SMC_HW_PERFORMANCE_LEVEL   dpmLevels[NISLANDS_MAX_SMC_PERFORMANCE_LEVELS_PER_SWSTATE - 1];
> +       uint8_t                             thermalProtectType;
> +       uint8_t                             systemFlags;
> +       uint8_t                             maxVDDCIndexInPPTable;
> +       uint8_t                             extraFlags;
> +       uint8_t                             highSMIO[NISLANDS_MAX_NO_VREG_STEPS];
> +       uint32_t                            lowSMIO[NISLANDS_MAX_NO_VREG_STEPS];
> +       NISLANDS_SMC_VOLTAGEMASKTABLE       voltageMaskTable;
> +       PP_NIslands_DPM2Parameters          dpm2Params;
> +       struct NISLANDS_SMC_SWSTATE_SINGLE  initialState;
> +       struct NISLANDS_SMC_SWSTATE_SINGLE  ACPIState;
> +       struct NISLANDS_SMC_SWSTATE_SINGLE  ULVState;
> +       NISLANDS_SMC_SWSTATE                driverState;
> +       NISLANDS_SMC_HW_PERFORMANCE_LEVEL   dpmLevels[NISLANDS_MAX_SMC_PERFORMANCE_LEVELS_PER_SWSTATE];
>  };
>
>  typedef struct NISLANDS_SMC_STATETABLE NISLANDS_SMC_STATETABLE;
> --
> 2.27.0
>
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