Re: [kvm-unit-tests PATCH v5 05/13] arm/arm64: gicv3: Set the LPI config and pending tables

From: Auger Eric <eric.auger@redhat.com>
To: Zenghui Yu <yuzenghui@huawei.com>,
	eric.auger.pro@gmail.com, maz@kernel.org,
	kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org,
	qemu-devel@nongnu.org, qemu-arm@nongnu.org
Cc: andre.przywara@arm.com, drjones@redhat.com,
	alexandru.elisei@arm.com, thuth@redhat.com,
	peter.maydell@linaro.org
Subject: Re: [kvm-unit-tests PATCH v5 05/13] arm/arm64: gicv3: Set the LPI config and pending tables
Date: Wed, 11 Mar 2020 10:07:32 +0100	[thread overview]
Message-ID: <97357581-9712-b467-764c-d32f354b6f3c@redhat.com> (raw)
In-Reply-To: <cd3bab7d-a585-b091-621c-0ae712b82b3c@huawei.com>

Hi Zenghui,

On 3/11/20 7:42 AM, Zenghui Yu wrote:
> Hi Eric,
> 
> On 2020/3/10 22:54, Eric Auger wrote:
>> Allocate the LPI configuration and per re-distributor pending table.
>> Set redistributor's PROPBASER and PENDBASER. The LPIs are enabled
>> by default in the config table.
>>
>> Also introduce a helper routine that allows to set the pending table
>> bit for a given LPI.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>>
>> ---
>>
>> v4 -> v5:
>> - Moved some reformattings previously done in
>>    "arm/arm64: ITS: its_enable_defaults", in this patch
>> - added assert(!gicv3_redist_base()) in gicv3_lpi_alloc_tables()
>> - revert for_each_present_cpu() change
>>
>> v2 -> v3:
>> - Move the helpers in lib/arm/gic-v3.c and prefix them with "gicv3_"
>>    and add _lpi prefix too
>>
>> v1 -> v2:
>> - remove memory attributes
>> ---
>>   lib/arm/asm/gic-v3.h | 15 +++++++++++++
>>   lib/arm/gic-v3.c     | 53 ++++++++++++++++++++++++++++++++++++++++++++
>>   2 files changed, 68 insertions(+)
>>
>> diff --git a/lib/arm/asm/gic-v3.h b/lib/arm/asm/gic-v3.h
>> index 47df051..064cc68 100644
>> --- a/lib/arm/asm/gic-v3.h
>> +++ b/lib/arm/asm/gic-v3.h
>> @@ -50,6 +50,15 @@
>>   #define MPIDR_TO_SGI_AFFINITY(cluster_id, level) \
>>       (MPIDR_AFFINITY_LEVEL(cluster_id, level) <<
>> ICC_SGI1R_AFFINITY_## level ## _SHIFT)
>>   +#define GICR_PROPBASER_IDBITS_MASK    (0x1f)
> 
> Again this can be dropped, but not a problem.
OK
> 
>> +
>> +#define GICR_PENDBASER_PTZ        BIT_ULL(62)
>> +
>> +#define LPI_PROP_GROUP1            (1 << 1)
>> +#define LPI_PROP_ENABLED        (1 << 0)
>> +#define LPI_PROP_DEFAULT_PRIO        0xa0
>> +#define LPI_PROP_DEFAULT        (LPI_PROP_DEFAULT_PRIO |
>> LPI_PROP_GROUP1 | LPI_PROP_ENABLED)
>> +
>>   #include <asm/arch_gicv3.h>
>>     #ifndef __ASSEMBLY__
>> @@ -66,6 +75,8 @@ struct gicv3_data {
>>       void *dist_base;
>>       void *redist_bases[GICV3_NR_REDISTS];
>>       void *redist_base[NR_CPUS];
>> +    u8 *lpi_prop;
>> +    void *lpi_pend[NR_CPUS];
>>       unsigned int irq_nr;
>>   };
>>   extern struct gicv3_data gicv3_data;
>> @@ -82,6 +93,10 @@ extern void gicv3_write_eoir(u32 irqstat);
>>   extern void gicv3_ipi_send_single(int irq, int cpu);
>>   extern void gicv3_ipi_send_mask(int irq, const cpumask_t *dest);
>>   extern void gicv3_set_redist_base(size_t stride);
>> +extern void gicv3_lpi_set_config(int n, u8 val);
>> +extern u8 gicv3_lpi_get_config(int n);
> 
> These two declarations can be dropped, and I think it's better to
> move their macro implementations here (they're now in patch #7).
> But also not a problem.
OK
> 
>> +extern void gicv3_lpi_set_clr_pending(int rdist, int n, bool set);
>> +extern void gicv3_lpi_alloc_tables(void);
>>     static inline void gicv3_do_wait_for_rwp(void *base)
>>   {
>> diff --git a/lib/arm/gic-v3.c b/lib/arm/gic-v3.c
>> index feecb5e..d752bd4 100644
>> --- a/lib/arm/gic-v3.c
>> +++ b/lib/arm/gic-v3.c
>> @@ -5,6 +5,7 @@
>>    */
>>   #include <asm/gic.h>
>>   #include <asm/io.h>
>> +#include <alloc_page.h>
>>     void gicv3_set_redist_base(size_t stride)
>>   {
>> @@ -147,3 +148,55 @@ void gicv3_ipi_send_single(int irq, int cpu)
>>       cpumask_set_cpu(cpu, &dest);
>>       gicv3_ipi_send_mask(irq, &dest);
>>   }
>> +
>> +#if defined(__aarch64__)
>> +
>> +/*
>> + * alloc_lpi_tables - Allocate LPI config and pending tables
>> + * and set PROPBASER (shared by all rdistributors) and per
>> + * redistributor PENDBASER.
>> + *
>> + * gicv3_set_redist_base() must be called before
>> + */
>> +void gicv3_lpi_alloc_tables(void)
>> +{
>> +    unsigned long n = SZ_64K >> PAGE_SHIFT;
>> +    unsigned long order = fls(n);
>> +    u64 prop_val;
>> +    int cpu;
>> +
>> +    assert(!gicv3_redist_base());
> 
> I guess you wanted assert(gicv3_redist_base())? With this confirmed,
damn, a last minute change I must have failed to test?! Indeed you're right.
> 
> Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Thanks!

> 
> 
> Thanks
> 
>> +
>> +    gicv3_data.lpi_prop = alloc_pages(order);
>> +
>> +    /* ID bits = 13, ie. up to 14b LPI INTID */
>> +    prop_val = (u64)(virt_to_phys(gicv3_data.lpi_prop)) | 13;
>> +
>> +    for_each_present_cpu(cpu) {
>> +        u64 pend_val;
>> +        void *ptr;
>> +
>> +        ptr = gicv3_data.redist_base[cpu];
>> +
>> +        writeq(prop_val, ptr + GICR_PROPBASER);
>> +
>> +        gicv3_data.lpi_pend[cpu] = alloc_pages(order);
>> +        pend_val = (u64)(virt_to_phys(gicv3_data.lpi_pend[cpu]));
>> +        writeq(pend_val, ptr + GICR_PENDBASER);
>> +    }
>> +}
>> +
>> +void gicv3_lpi_set_clr_pending(int rdist, int n, bool set)
>> +{
>> +    u8 *ptr = gicv3_data.lpi_pend[rdist];
>> +    u8 mask = 1 << (n % 8), byte;
>> +
>> +    ptr += (n / 8);
>> +    byte = *ptr;
>> +    if (set)
>> +        byte |=  mask;
>> +    else
>> +        byte &= ~mask;
>> +    *ptr = byte;
>> +}
>> +#endif /* __aarch64__ */
>>
> 
> 