[PATCH 06/11] irqchip/gic-v3-its: Kill its->device_ids and use TYPER copy instead

Marc Zyngier
2019-11-05T16:23:22Z

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>
---
drivers/irqchip/irq-gic-v3-its.c | 24 +++++++++++++-----------
include/linux/irqchip/arm-gic-v3.h | 2 +-
2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 161831e2b7ac..9b1c53a5db4a 100644
--- 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

@@ -1953,9 +1953,9 @@ 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;
@@ -2001,7 +2001,7 @@ 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:
@@ -2392,7 +2392,7 @@ 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);
}
@@ -3245,8 +3245,9 @@ 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;
@@ -3301,8 +3302,10 @@ 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;
@@ -3535,7 +3538,7 @@ 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);
@@ -3636,7 +3639,6 @@ 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 4bce7a904075..b6514e8893bf 100644
--- 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)
--
2.20.1