Re: [PATCH v3 15/17] driver/cpufreq: enable Hygon support to cpufreq driver

From: Rafael J. Wysocki
Date: Sun Aug 12 2018 - 05:55:48 EST


On Sat, Aug 11, 2018 at 3:36 PM Pu Wen <puwen@xxxxxxxx> wrote:
>
> Enable ACPI cpufreq driver support for Hygon by adding family ID check
> along with AMD.
>
> As Hygon platforms have SMBus device(PCI device ID 0x790b), enable Hygon
> support to function amd_freq_sensitivity_init().
>
> Signed-off-by: Pu Wen <puwen@xxxxxxxx>

Is there any technical difference between HYGON and AMD?

You seem to be mechanically adding X86_VENDOR_HYGON wherever
X86_VENDOR_AMD is used.

> ---
> drivers/cpufreq/acpi-cpufreq.c | 5 +++++
> drivers/cpufreq/amd_freq_sensitivity.c | 9 +++++++--
> 2 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
> index b61f4ec..d62fd37 100644
> --- a/drivers/cpufreq/acpi-cpufreq.c
> +++ b/drivers/cpufreq/acpi-cpufreq.c
> @@ -61,6 +61,7 @@ enum {
>
> #define INTEL_MSR_RANGE (0xffff)
> #define AMD_MSR_RANGE (0x7)
> +#define HYGON_MSR_RANGE (0x7)
>
> #define MSR_K7_HWCR_CPB_DIS (1ULL << 25)
>
> @@ -95,6 +96,7 @@ static bool boost_state(unsigned int cpu)
> rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
> msr = lo | ((u64)hi << 32);
> return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
> + case X86_VENDOR_HYGON:
> case X86_VENDOR_AMD:
> rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
> msr = lo | ((u64)hi << 32);
> @@ -113,6 +115,7 @@ static int boost_set_msr(bool enable)
> msr_addr = MSR_IA32_MISC_ENABLE;
> msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
> break;
> + case X86_VENDOR_HYGON:
> case X86_VENDOR_AMD:
> msr_addr = MSR_K7_HWCR;
> msr_mask = MSR_K7_HWCR_CPB_DIS;
> @@ -225,6 +228,8 @@ static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
>
> if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
> msr &= AMD_MSR_RANGE;
> + else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
> + msr &= HYGON_MSR_RANGE;
> else
> msr &= INTEL_MSR_RANGE;
>
> diff --git a/drivers/cpufreq/amd_freq_sensitivity.c b/drivers/cpufreq/amd_freq_sensitivity.c
> index be926d9..4ac7c3c 100644
> --- a/drivers/cpufreq/amd_freq_sensitivity.c
> +++ b/drivers/cpufreq/amd_freq_sensitivity.c
> @@ -111,11 +111,16 @@ static int __init amd_freq_sensitivity_init(void)
> {
> u64 val;
> struct pci_dev *pcidev;
> + unsigned int pci_vendor;
>
> - if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
> + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
> + pci_vendor = PCI_VENDOR_ID_AMD;
> + else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
> + pci_vendor = PCI_VENDOR_ID_HYGON;
> + else
> return -ENODEV;
>
> - pcidev = pci_get_device(PCI_VENDOR_ID_AMD,
> + pcidev = pci_get_device(pci_vendor,
> PCI_DEVICE_ID_AMD_KERNCZ_SMBUS, NULL);
>
> if (!pcidev) {
> --
> 2.7.4
>