Re: [PATCH] MIPS: X1830: Add X1830 system type.

[Zhou Yanjie <zhouyanjie@zoho.com>]

Hi Paul,

On 2019年11月28日 01:16, Paul Cercueil wrote:
> Hi Zhou,
>
>
> Le mar., nov. 26, 2019 at 14:17, Zhou Yanjie <zhouyanjie@zoho.com> a 
> écrit :
>> Add X1830 system type for cat /proc/cpuinfo to give out X1830.
>>
>> Signed-off-by: Zhou Yanjie <zhouyanjie@zoho.com>
>> ---
>>  arch/mips/include/asm/bootinfo.h |  1 +
>>  arch/mips/include/asm/cpu.h      |  5 ++--
>>  arch/mips/jz4740/setup.c         |  4 +++
>>  arch/mips/kernel/cpu-probe.c     | 65 
>> ++++++++++++++++++++++------------------
>>  4 files changed, 44 insertions(+), 31 deletions(-)
>>
>> diff --git a/arch/mips/include/asm/bootinfo.h 
>> b/arch/mips/include/asm/bootinfo.h
>> index 34d6222..07f4cfe 100644
>> --- a/arch/mips/include/asm/bootinfo.h
>> +++ b/arch/mips/include/asm/bootinfo.h
>> @@ -82,6 +82,7 @@ enum loongson_machine_type {
>>  #define  MACH_INGENIC_JZ4770    2    /* JZ4770 SOC        */
>>  #define  MACH_INGENIC_JZ4780    3    /* JZ4780 SOC        */
>>  #define  MACH_INGENIC_X1000        4    /* X1000 SOC        */
>> +#define  MACH_INGENIC_X1830        5    /* X1830 SOC        */
>>
>>  extern char *system_type;
>>  const char *get_system_type(void);
>> diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h
>> index 7fddcb8..fa7c1e8 100644
>> --- a/arch/mips/include/asm/cpu.h
>> +++ b/arch/mips/include/asm/cpu.h
>> @@ -46,7 +46,7 @@
>>  #define PRID_COMP_NETLOGIC    0x0c0000
>>  #define PRID_COMP_CAVIUM    0x0d0000
>>  #define PRID_COMP_LOONGSON    0x140000
>> -#define PRID_COMP_INGENIC_D0    0xd00000    /* JZ4740, JZ4750 */
>> +#define PRID_COMP_INGENIC_D0    0xd00000    /* JZ4740, JZ4750, X1830 */
>>  #define PRID_COMP_INGENIC_D1    0xd10000    /* JZ4770, JZ4775, X1000 */
>>  #define PRID_COMP_INGENIC_E1    0xe10000    /* JZ4780 */
>>
>> @@ -183,7 +183,8 @@
>>   * These are the PRID's for when 23:16 == PRID_COMP_INGENIC_*
>>   */
>>
>> -#define PRID_IMP_XBURST           0x0200
>> +#define PRID_IMP_XBURST_REV1    0x0200    /* XBurst with MXU SIMD 
>> ISA        */
>> +#define PRID_IMP_XBURST_REV2    0x0100    /* XBurst with MXU2 SIMD 
>> ISA    */
>>
>>  /*
>>   * These are the PRID's for when 23:16 == PRID_COMP_NETLOGIC
>> diff --git a/arch/mips/jz4740/setup.c b/arch/mips/jz4740/setup.c
>> index dc8ee21..880c268 100644
>> --- a/arch/mips/jz4740/setup.c
>> +++ b/arch/mips/jz4740/setup.c
>> @@ -44,6 +44,8 @@ static void __init jz4740_detect_mem(void)
>>
>>  static unsigned long __init get_board_mach_type(const void *fdt)
>>  {
>> +    if (!fdt_node_check_compatible(fdt, 0, "ingenic,x1830"))
>> +        return MACH_INGENIC_X1830;
>>      if (!fdt_node_check_compatible(fdt, 0, "ingenic,x1000"))
>>          return MACH_INGENIC_X1000;
>>      if (!fdt_node_check_compatible(fdt, 0, "ingenic,jz4780"))
>> @@ -86,6 +88,8 @@ void __init device_tree_init(void)
>>  const char *get_system_type(void)
>>  {
>>      switch (mips_machtype) {
>> +    case MACH_INGENIC_X1830:
>> +        return "X1830";
>>      case MACH_INGENIC_X1000:
>>          return "X1000";
>>      case MACH_INGENIC_JZ4780:
>> diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
>> index 8abadfe..94b3cc5 100644
>> --- a/arch/mips/kernel/cpu-probe.c
>> +++ b/arch/mips/kernel/cpu-probe.c
>> @@ -1948,10 +1948,8 @@ static inline void cpu_probe_ingenic(struct 
>> cpuinfo_mips *c, unsigned int cpu)
>>      BUG_ON(!__builtin_constant_p(cpu_has_counter) || cpu_has_counter);
>>
>>      switch (c->processor_id & PRID_IMP_MASK) {
>> -    case PRID_IMP_XBURST:
>> -        c->cputype = CPU_XBURST;
>> -        c->writecombine = _CACHE_UNCACHED_ACCELERATED;
>> -        __cpu_name[cpu] = "Ingenic JZRISC";
>> +    case PRID_IMP_XBURST_REV1:
>> +
>>          /*
>>           * The XBurst core by default attempts to avoid branch target
>>           * buffer lookups by detecting & special casing loops. This
>> @@ -1959,34 +1957,43 @@ static inline void cpu_probe_ingenic(struct 
>> cpuinfo_mips *c, unsigned int cpu)
>>           * Set cp0 config7 bit 4 to disable this feature.
>>           */
>>          set_c0_config7(MIPS_CONF7_BTB_LOOP_EN);
>> -        break;
>> -    default:
>> -        panic("Unknown Ingenic Processor ID!");
>> -        break;
>> -    }
>>
>> -    switch (c->processor_id & PRID_COMP_MASK) {
>> -    /*
>> -     * The config0 register in the XBurst CPUs with a processor ID of
>> -     * PRID_COMP_INGENIC_D1 has an abandoned huge page tlb mode, this
>> -     * mode is not compatible with the MIPS standard, it will cause
>> -     * tlbmiss and into an infinite loop (line 21 in the tlb-funcs.S)
>> -     * when starting the init process. After chip reset, the default
>> -     * is HPTLB mode, Write 0xa9000000 to cp0 register 5 sel 4 to
>> -     * switch back to VTLB mode to prevent getting stuck.
>> -     */
>> -    case PRID_COMP_INGENIC_D1:
>> -        write_c0_page_ctrl(XBURST_PAGECTRL_HPTLB_DIS);
>> -        break;
>> -    /*
>> -     * The config0 register in the XBurst CPUs with a processor ID of
>> -     * PRID_COMP_INGENIC_D0 report themselves as MIPS32r2 compatible,
>> -     * but they don't actually support this ISA.
>> -     */
>> -    case PRID_COMP_INGENIC_D0:
>> -        c->isa_level &= ~MIPS_CPU_ISA_M32R2;
>> +        switch (c->processor_id & PRID_COMP_MASK) {
>> +
>> +        /*
>> +         * The config0 register in the XBurst CPUs with a processor 
>> ID of
>> +         * PRID_COMP_INGENIC_D0 report themselves as MIPS32r2 
>> compatible,
>> +         * but they don't actually support this ISA.
>> +         */
>> +        case PRID_COMP_INGENIC_D0:
>> +            c->isa_level &= ~MIPS_CPU_ISA_M32R2;
>> +            break;
>> +
>> +        /*
>> +         * The config0 register in the XBurst CPUs with a processor 
>> ID of
>> +         * PRID_COMP_INGENIC_D1 has an abandoned huge page tlb mode, 
>> this
>> +         * mode is not compatible with the MIPS standard, it will cause
>> +         * tlbmiss and into an infinite loop (line 21 in the 
>> tlb-funcs.S)
>> +         * when starting the init process. After chip reset, the 
>> default
>> +         * is HPTLB mode, Write 0xa9000000 to cp0 register 5 sel 4 to
>> +         * switch back to VTLB mode to prevent getting stuck.
>> +         */
>> +        case PRID_COMP_INGENIC_D1:
>> +            write_c0_page_ctrl(XBURST_PAGECTRL_HPTLB_DIS);
>> +            break;
>> +
>> +        default:
>> +            break;
>> +        }
>
> I see no "break" here. If that's intended, please add a /* 
> fall-through */ comment here. It will prevent GCC from issuing a 
> warning when -Wimplicit-fallthrough is used.
>

Sure, I will add it in v2.

>> +
>> +    case PRID_IMP_XBURST_REV2:
>> +        c->cputype = CPU_XBURST;
>> +        c->writecombine = _CACHE_UNCACHED_ACCELERATED;
>> +        __cpu_name[cpu] = "Ingenic XBurst";
>
> The CPU name switched from "Ingenic JZRISC" to "Ingenic XBurst". If 
> that's intended (I believe it is) please mention it in the commit 
> message.
>

Ok, I will mention it in the commit message when I send v2.

Thanks and best regards!

> Cheers,
> -Paul
>
>>          break;
>> +
>>      default:
>> +        panic("Unknown Ingenic Processor ID!");
>>          break;
>>      }
>>  }
>> -- 
>> 2.7.4
>>
>>
>
>