The following commit has been merged into the irq/core branch of tip:
Commit-ID: 4c601685434fd34f9fa328c861241d8433606c4c
Gitweb: https://git.kernel.org/tip/4c601685434fd34f9fa328c861241d8433606c4c
Author: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
AuthorDate: Mon, 27 Nov 2023 16:52:13 +01:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Fri, 08 Dec 2023 22:06:36 +01:00
irqchip/qcom-mpm: Support passing a slice of SRAM as reg space
The MPM hardware is accessible from the ARM CPUs through a shared memory
region (RPM MSG RAM) which is also concurrently accessed by other kinds of
cores on the system like modem, ADSP etc.
Modeling this relation in a (somewhat) sane manner in the device tree
requires to
- either present the MPM as a child of said memory region, which
makes little sense, as a mapped memory carveout is not a bus.
- define nodes which bleed their register spaces into one another
- or passing their slice of the MSG RAM through a property
Go with the third option and add a way to map a region passed through the
"qcom,rpm-msg-ram" property as register space for the MPM interrupt
controller.
The current way of using 'reg' is preserved for backwards compatibility
reasons.
[ tglx: Massaged changelog ]
Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>
Acked-by: Shawn Guo <shawn.guo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230328-topic-msgram_mpm-v7-2-6ee2bfeaac2c@xxxxxxxxxx
---
drivers/irqchip/irq-qcom-mpm.c | 26 +++++++++++++++++++++++---
1 file changed, 23 insertions(+), 3 deletions(-)
diff --git a/drivers/irqchip/irq-qcom-mpm.c b/drivers/irqchip/irq-qcom-mpm.c
index 7124565..cda5838 100644
--- a/drivers/irqchip/irq-qcom-mpm.c
+++ b/drivers/irqchip/irq-qcom-mpm.c
@@ -14,6 +14,7 @@
#include <linux/mailbox_client.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
@@ -322,8 +323,10 @@ static int qcom_mpm_init(struct device_node *np, struct device_node *parent)
struct device *dev = &pdev->dev;
struct irq_domain *parent_domain;
struct generic_pm_domain *genpd;
+ struct device_node *msgram_np;
struct qcom_mpm_priv *priv;
unsigned int pin_cnt;
+ struct resource res;
int i, irq;
int ret;
@@ -374,9 +377,26 @@ static int qcom_mpm_init(struct device_node *np, struct device_node *parent)
raw_spin_lock_init(&priv->lock);
- priv->base = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(priv->base))
- return PTR_ERR(priv->base);
+ /* If we have a handle to an RPM message ram partition, use it. */
+ msgram_np = of_parse_phandle(np, "qcom,rpm-msg-ram", 0);
+ if (msgram_np) {
+ ret = of_address_to_resource(msgram_np, 0, &res);
+ if (ret) {
+ of_node_put(msgram_np);
+ return ret;
+ }
+
+ /* Don't use devm_ioremap_resource, as we're accessing a shared region. */
+ priv->base = devm_ioremap(dev, res.start, resource_size(&res));
+ of_node_put(msgram_np);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+ } else {
+ /* Otherwise, fall back to simple MMIO. */
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+ }
for (i = 0; i < priv->reg_stride; i++) {
qcom_mpm_write(priv, MPM_REG_ENABLE, i, 0);
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