Re: [Qemu-devel] [kvm-unit-tests PATCH 2/4] arm/arm64: GICv2: add GICD_IPRIORITYR testing

[Auger Eric]

Hi Andre,
On 18/11/2016 15:02, Andrew Jones wrote:
> On Thu, Nov 17, 2016 at 05:57:50PM +0000, Andre Przywara wrote:
>> Some tests for the IPRIORITY registers. The significant number of bits
>> is IMPLEMENTATION DEFINED, but should be the same for every IRQ.
>> Also these registers must be byte-accessible.
>> Check that accesses beyond the implemented IRQ limit are actually
>> read-as-zero/write-ignore.
>>
>> Signed-off-by: Andre Przywara <address@hidden>
>> ---
>>  arm/gic.c | 72 
>> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 72 insertions(+)
>>
>> diff --git a/arm/gic.c b/arm/gic.c
>> index ba2585b..a27da2c 100644
>> --- a/arm/gic.c
>> +++ b/arm/gic.c
>> @@ -327,6 +327,76 @@ static bool test_typer_v2(uint32_t reg)
>>      return true;
>>  }
>>  
>> +#define BYTE(reg32, byte) (((reg32) >> ((byte) * 8)) & 0xff)
>> +#define REPLACE_BYTE(reg32, byte, new) (((reg32) & ~(0xff << ((byte) * 8))) 
>> |\
>> +                                    ((new) << ((byte) * 8)))
>> +
>> +static bool test_priorities(int nr_irqs, void *priptr)
>> +{
>> +    u32 orig_prio, reg, pri_bits;
>> +    u32 pri_mask, pattern;
>> +
>> +    orig_prio = readl(priptr + 32);
>> +    report_prefix_push("IPRIORITYR");
>> +
>> +    /*
>> +     * Determine implemented number of priority bits by writing all 1's
>> +     * and checking the number of cleared bits in the value read back.
>> +     */
>> +    writel(0xffffffff, priptr + 32);
>> +    pri_mask = readl(priptr + 32);
>> +
>> +    reg = ~pri_mask;
>> +    report("consistent priority masking (0x%08x)",
>> +           (((reg >> 16) == (reg & 0xffff)) &&
>> +            ((reg & 0xff) == ((reg >> 8) & 0xff))), pri_mask);
>> +
>> +    reg = reg & 0xff;
>> +    for (pri_bits = 8; reg & 1; reg >>= 1, pri_bits--)
>> +            ;
>> +    report("implements at least 4 priority bits (%d)",
>> +           pri_bits >= 4, pri_bits);
>> +
>> +    pattern = 0;
>> +    writel(pattern, priptr + 32);
>> +    report("clearing priorities", readl(priptr + 32) == pattern);
>> +
>> +    pattern = 0xffffffff;
>> +    writel(pattern, priptr + 32);
>> +    report("filling priorities",
>> +           readl(priptr + 32) == (pattern & pri_mask));
what's the point to re-do that check?
>> +
>> +    report("accesses beyond limit RAZ/WI",
>> +           test_readonly_32(priptr + nr_irqs, true));
>> +
>> +    writel(pattern, priptr + nr_irqs - 4);
>> +    report("accessing last SPIs",
>> +           readl(priptr + nr_irqs - 4) == (pattern & pri_mask));
>> +
>> +    pattern = 0xff7fbf3f;
>> +    writel(pattern, priptr + 32);
>> +    report("priorities are preserved",
>> +           readl(priptr + 32) == (pattern & pri_mask));
>> +
>> +    /*
>> +     * The PRIORITY registers are byte accessible, do a byte-wide
>> +     * read and write of known content to check for this.
>> +     */
>> +    reg = readb(priptr + 33);
>> +    report("byte reads successful (0x%08x => 0x%02x)",
>> +           reg == (BYTE(pattern, 1) & pri_mask), pattern & pri_mask, reg);
>> +
>> +    pattern = REPLACE_BYTE(pattern, 2, 0x1f);
>> +    writeb(BYTE(pattern, 2), priptr + 34);
>> +    reg = readl(priptr + 32);
>> +    report("byte writes successful (0x%02x => 0x%08x)",
>> +           reg == (pattern & pri_mask), BYTE(pattern, 2) & pri_mask, reg);
>> +
>> +    report_prefix_pop();
>> +    writel(orig_prio, priptr + 32);
>> +    return true;
> 
> Might be nice to have FIRST_SPI and maybe LAST_SPI macros to avoid all
> the +32's
> 
> This function always returns true, so it can be a void.
> 
>> +}
>> +
>>  static int gic_test_mmio(int gic_version)
>>  {
>>      u32 reg;
>> @@ -364,6 +434,8 @@ static int gic_test_mmio(int gic_version)
>>             test_readonly_32(idreg, false),
>>             reg);
>>  
>> +    test_priorities(nr_irqs, gic_dist_base + GICD_IPRIORITYR);
> 
> Feel free to add state like nr_irqs and dist_base to the gic struct
> defined in arm/gic.c. That struct should provide the abstraction
> needed to handle both gicv2 and gicv3 and contain anything that the
> test functions need to refer to frequently. Using it should help
> reduce the amount of parameters passed around.
> 
>> +
>>      return 0;
>>  }
>>  
>> -- 
>> 2.9.0
> 
> Otherwise looks good to me
same: Reviewed-by: Eric Auger <address@hidden>

Thanks

Eric

> 
> Reviewed-by: Andrew Jones <address@hidden>
>>
>>
>