Re: [kvm-unit-tests PATCH v3 06/14] arm/arm64: gicv3: Set the LPI config and pending tables

[Auger Eric <eric.auger@redhat.com>]

Hi Zenghui,

On 2/7/20 3:12 AM, Zenghui Yu wrote:
> Hi Eric,
> 
> On 2020/1/28 18:34, 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>
>>
>> ---
>>
>> 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 | 16 +++++++++++
>>   lib/arm/gic-v3.c     | 64 ++++++++++++++++++++++++++++++++++++++++++++
>>   2 files changed, 80 insertions(+)
>>
>> diff --git a/lib/arm/asm/gic-v3.h b/lib/arm/asm/gic-v3.h
>> index ffb2e26..ec2a6f0 100644
>> --- a/lib/arm/asm/gic-v3.h
>> +++ b/lib/arm/asm/gic-v3.h
>> @@ -48,6 +48,16 @@
>>   #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)
> 
> This is not being used.  You can use it when calculating prop_val
> or just drop it.
yep dropped it.
> 
>> +
>> +#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__
>> @@ -64,6 +74,8 @@ struct gicv3_data {
>>       void *dist_base;
>>       void *redist_bases[GICV3_NR_REDISTS];
>>       void *redist_base[NR_CPUS];
>> +    void *lpi_prop;
>> +    void *lpi_pend[NR_CPUS];
>>       unsigned int irq_nr;
>>   };
>>   extern struct gicv3_data gicv3_data;
>> @@ -80,6 +92,10 @@ 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);
>> +extern void gicv3_lpi_set_pending_table_bit(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..c33f883 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 +148,66 @@ 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 */
>> +void gicv3_lpi_alloc_tables(void)
>> +{
>> +    unsigned long n = SZ_64K >> PAGE_SHIFT;
>> +    unsigned long order = fls(n);
>> +    u64 prop_val;
>> +    int cpu;
>> +
>> +    gicv3_data.lpi_prop = (void *)virt_to_phys(alloc_pages(order));
>> +
>> +    /* ID bits = 13, ie. up to 14b LPI INTID */
>> +    prop_val = (u64)gicv3_data.lpi_prop | 13;
>> +
>> +    /*
>> +     * Allocate pending tables for each redistributor
>> +     * and set PROPBASER and PENDBASER
>> +     */
>> +    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] = (void
>> *)virt_to_phys(alloc_pages(order));
>> +
>> +        pend_val = (u64)gicv3_data.lpi_pend[cpu];
>> +
>> +        writeq(pend_val, ptr + GICR_PENDBASER);
>> +    }
>> +}
>> +
>> +void gicv3_lpi_set_config(int n, u8 value)
>> +{
>> +    u8 *entry = (u8 *)(gicv3_data.lpi_prop + (n - 8192));
> 
> But this is actually the *physical* address, shouldn't it be
> converted by phys_to_virt() before reading/writing something?
> Like what you've done for the 'lpi_pend[rdist]' before writing
> pending bit.  Or I'm missing some points here?
Agreed! Thanks

Eric
> 
>> +
>> +    *entry = value;
>> +}
>> +
>> +u8 gicv3_lpi_get_config(int n)
>> +{
>> +    u8 *entry = (u8 *)(gicv3_data.lpi_prop + (n - 8192));
> 
> The same as above.
> 
> 
> Thanks,
> Zenghui
> 
>> +
>> +    return *entry;
>> +}
>> +
>> +void gicv3_lpi_set_pending_table_bit(int rdist, int n, bool set)
>> +{
>> +    u8 *ptr = phys_to_virt((phys_addr_t)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__ */
>>
>