irqchip/gic-v3-its: Kill its->device_ids and use TYPER copy instead

Now that we have a copy of TYPER in the ITS structure, rely on this
to provide the same service as its->device_ids, which gets axed.
Errata workarounds are now updating the cached fields instead of
requiring a separate field in the ITS structure.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191027144234.8395-7-maz@kernel.org
Link: https://lore.kernel.org/r/20191108165805.3071-7-maz@kernel.org

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index c3a1e47..e8aeb07 100644 (file)
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -109,7 +109,6 @@ struct its_node {
        struct list_head        its_device_list;
        u64                     flags;
        unsigned long           list_nr;
-       u32                     device_ids;
        int                     numa_node;
        unsigned int            msi_domain_flags;
        u32                     pre_its_base; /* for Socionext Synquacer */
@@ -117,6 +116,7 @@ struct its_node {
 };
 
 #define is_v4(its)             (!!((its)->typer & GITS_TYPER_VLPIS))
+#define device_ids(its)                (FIELD_GET(GITS_TYPER_DEVBITS, (its)->typer) + 1)
 
 #define ITS_ITT_ALIGN          SZ_256
 
@@ -1956,9 +1956,9 @@ static bool its_parse_indirect_baser(struct its_node *its,
        if (new_order >= MAX_ORDER) {
                new_order = MAX_ORDER - 1;
                ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz);
-               pr_warn("ITS@%pa: %s Table too large, reduce ids %u->%u\n",
+               pr_warn("ITS@%pa: %s Table too large, reduce ids %llu->%u\n",
                        &its->phys_base, its_base_type_string[type],
-                       its->device_ids, ids);
+                       device_ids(its), ids);
        }
 
        *order = new_order;
@@ -2004,7 +2004,7 @@ static int its_alloc_tables(struct its_node *its)
                case GITS_BASER_TYPE_DEVICE:
                        indirect = its_parse_indirect_baser(its, baser,
                                                            psz, &order,
-                                                           its->device_ids);
+                                                           device_ids(its));
                        break;
 
                case GITS_BASER_TYPE_VCPU:
@@ -2395,7 +2395,7 @@ static bool its_alloc_device_table(struct its_node *its, u32 dev_id)
 
        /* Don't allow device id that exceeds ITS hardware limit */
        if (!baser)
-               return (ilog2(dev_id) < its->device_ids);
+               return (ilog2(dev_id) < device_ids(its));
 
        return its_alloc_table_entry(its, baser, dev_id);
 }
@@ -3247,8 +3247,9 @@ static bool __maybe_unused its_enable_quirk_cavium_22375(void *data)
 {
        struct its_node *its = data;
 
-       /* erratum 22375: only alloc 8MB table size */
-       its->device_ids = 0x14;         /* 20 bits, 8MB */
+       /* erratum 22375: only alloc 8MB table size (20 bits) */
+       its->typer &= ~GITS_TYPER_DEVBITS;
+       its->typer |= FIELD_PREP(GITS_TYPER_DEVBITS, 20 - 1);
        its->flags |= ITS_FLAGS_WORKAROUND_CAVIUM_22375;
 
        return true;
@@ -3303,8 +3304,10 @@ static bool __maybe_unused its_enable_quirk_socionext_synquacer(void *data)
                its->get_msi_base = its_irq_get_msi_base_pre_its;
 
                ids = ilog2(pre_its_window[1]) - 2;
-               if (its->device_ids > ids)
-                       its->device_ids = ids;
+               if (device_ids(its) > ids) {
+                       its->typer &= ~GITS_TYPER_DEVBITS;
+                       its->typer |= FIELD_PREP(GITS_TYPER_DEVBITS, ids - 1);
+               }
 
                /* the pre-ITS breaks isolation, so disable MSI remapping */
                its->msi_domain_flags &= ~IRQ_DOMAIN_FLAG_MSI_REMAP;
@@ -3537,7 +3540,7 @@ static int its_init_vpe_domain(void)
        }
 
        /* Use the last possible DevID */
-       devid = GENMASK(its->device_ids - 1, 0);
+       devid = GENMASK(device_ids(its) - 1, 0);
        vpe_proxy.dev = its_create_device(its, devid, entries, false);
        if (!vpe_proxy.dev) {
                kfree(vpe_proxy.vpes);
@@ -3638,7 +3641,6 @@ static int __init its_probe_one(struct resource *res,
        its->typer = typer;
        its->base = its_base;
        its->phys_base = res->start;
-       its->device_ids = GITS_TYPER_DEVBITS(typer);
        if (is_v4(its)) {
                if (!(typer & GITS_TYPER_VMOVP)) {
                        err = its_compute_its_list_map(res, its_base);

diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index 4bce7a9..b6514e8 100644 (file)
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -337,7 +337,7 @@
 #define GITS_TYPER_ITT_ENTRY_SIZE      GENMASK_ULL(7, 4)
 #define GITS_TYPER_IDBITS_SHIFT                8
 #define GITS_TYPER_DEVBITS_SHIFT       13
-#define GITS_TYPER_DEVBITS(r)          ((((r) >> GITS_TYPER_DEVBITS_SHIFT) & 0x1f) + 1)
+#define GITS_TYPER_DEVBITS             GENMASK_ULL(17, 13)
 #define GITS_TYPER_PTA                 (1UL << 19)
 #define GITS_TYPER_HCC_SHIFT           24
 #define GITS_TYPER_HCC(r)              (((r) >> GITS_TYPER_HCC_SHIFT) & 0xff)