[PATCH v5 07/23] irqchip/gic-v4.1: Map the ITS SGIR register page

Marc Zyngier
2020-03-04T20:34:47Z

One of the new features of GICv4.1 is to allow virtual SGIs to be
directly signaled to a VPE. For that, the ITS has grown a new
64kB page containing only a single register that is used to
signal a SGI to a given VPE.

Add a second mapping covering this new 64kB range, and take this
opportunity to limit the original mapping to 64kB, which is enough
to cover the span of the ITS registers.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
---
drivers/irqchip/irq-gic-v3-its.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index bcc1a0957cda..54d6fdf7a28e 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -96,6 +96,7 @@ struct its_node {
struct mutex dev_alloc_lock;
struct list_head entry;
void __iomem *base;
+ void __iomem *sgir_base;
phys_addr_t phys_base;
struct its_cmd_block *cmd_base;
struct its_cmd_block *cmd_write;
@@ -4456,7 +4457,7 @@ static int __init its_probe_one(struct resource *res,
struct page *page;
int err;

- its_base = ioremap(res->start, resource_size(res));
+ its_base = ioremap(res->start, SZ_64K);
if (!its_base) {
pr_warn("ITS@%pa: Unable to map ITS registers\n", &res->start);
return -ENOMEM;
@@ -4507,6 +4508,13 @@ static int __init its_probe_one(struct resource *res,

if (is_v4_1(its)) {
u32 svpet = FIELD_GET(GITS_TYPER_SVPET, typer);
+
+ its->sgir_base = ioremap(res->start + SZ_128K, SZ_64K);
+ if (!its->sgir_base) {
+ err = -ENOMEM;
+ goto out_free_its;
+ }
+
its->mpidr = readl_relaxed(its_base + GITS_MPIDR);

pr_info("ITS@%pa: Using GICv4.1 mode %08x %08x\n",
@@ -4520,7 +4528,7 @@ static int __init its_probe_one(struct resource *res,
get_order(ITS_CMD_QUEUE_SZ));
if (!page) {
err = -ENOMEM;
- goto out_free_its;
+ goto out_unmap_sgir;
}
its->cmd_base = (void *)page_address(page);
its->cmd_write = its->cmd_base;
@@ -4587,6 +4595,9 @@ static int __init its_probe_one(struct resource *res,
its_free_tables(its);
out_free_cmd:
free_pages((unsigned long)its->cmd_base, get_order(ITS_CMD_QUEUE_SZ));
+out_unmap_sgir:
+ if (its->sgir_base)
+ iounmap(its->sgir_base);
out_free_its:
kfree(its);
out_unmap:
--
2.20.1