[PATCH v2 1/8] firmware: arm_scmi: Introduce setup_shmem_iomap

From: Cristian Marussi
Date: Wed Jul 10 2024 - 13:32:43 EST


From: Peng Fan <peng.fan@xxxxxxx>

To get the address of shmem could be generalized by introducing
setup_shmem_iomap. Then the duplicated code in mailbox.c, optee.c
and smc.c could be dropped.

Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
[ Cristian: use OF __free and make use of the new helper also in smc.c ]
Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
v1 --> v2
- add optional *res param to setup_shmem_iomap
- fixed __iomem tagging
- use OF __free cleanup.h magic to of_put()
---
drivers/firmware/arm_scmi/common.h | 2 ++
drivers/firmware/arm_scmi/mailbox.c | 27 +++----------------
drivers/firmware/arm_scmi/optee.c | 35 +++---------------------
drivers/firmware/arm_scmi/shmem.c | 41 +++++++++++++++++++++++++++++
drivers/firmware/arm_scmi/smc.c | 27 ++++---------------
5 files changed, 56 insertions(+), 76 deletions(-)

diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 4b8c5250cdb5..d5e80a24e2d4 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -327,6 +327,8 @@ bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
struct scmi_xfer *xfer);
bool shmem_channel_free(struct scmi_shared_mem __iomem *shmem);
bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem);
+void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo, struct device *dev,
+ bool tx, struct resource *res);

/* declarations for message passing transports */
struct scmi_msg_payld;
diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
index 0219a12e3209..886fc4eedb4a 100644
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/mailbox.c
@@ -178,11 +178,8 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
const char *desc = tx ? "Tx" : "Rx";
struct device *cdev = cinfo->dev;
struct scmi_mailbox *smbox;
- struct device_node *shmem;
- int ret, a2p_rx_chan, p2a_chan, p2a_rx_chan, idx = tx ? 0 : 1;
+ int ret, a2p_rx_chan, p2a_chan, p2a_rx_chan;
struct mbox_client *cl;
- resource_size_t size;
- struct resource res;

ret = mailbox_chan_validate(cdev, &a2p_rx_chan, &p2a_chan, &p2a_rx_chan);
if (ret)
@@ -195,25 +192,9 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
if (!smbox)
return -ENOMEM;

- shmem = of_parse_phandle(cdev->of_node, "shmem", idx);
- if (!of_device_is_compatible(shmem, "arm,scmi-shmem")) {
- of_node_put(shmem);
- return -ENXIO;
- }
-
- ret = of_address_to_resource(shmem, 0, &res);
- of_node_put(shmem);
- if (ret) {
- dev_err(cdev, "failed to get SCMI %s shared memory\n", desc);
- return ret;
- }
-
- size = resource_size(&res);
- smbox->shmem = devm_ioremap(dev, res.start, size);
- if (!smbox->shmem) {
- dev_err(dev, "failed to ioremap SCMI %s shared memory\n", desc);
- return -EADDRNOTAVAIL;
- }
+ smbox->shmem = setup_shmem_iomap(cinfo, dev, tx, NULL);
+ if (IS_ERR(smbox->shmem))
+ return PTR_ERR(smbox->shmem);

cl = &smbox->cl;
cl->dev = cdev;
diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c
index 4e7944b91e38..d9458ef7378a 100644
--- a/drivers/firmware/arm_scmi/optee.c
+++ b/drivers/firmware/arm_scmi/optee.c
@@ -368,38 +368,11 @@ static int setup_dynamic_shmem(struct device *dev, struct scmi_optee_channel *ch
static int setup_static_shmem(struct device *dev, struct scmi_chan_info *cinfo,
struct scmi_optee_channel *channel)
{
- struct device_node *np;
- resource_size_t size;
- struct resource res;
- int ret;
-
- np = of_parse_phandle(cinfo->dev->of_node, "shmem", 0);
- if (!of_device_is_compatible(np, "arm,scmi-shmem")) {
- ret = -ENXIO;
- goto out;
- }
-
- ret = of_address_to_resource(np, 0, &res);
- if (ret) {
- dev_err(dev, "Failed to get SCMI Tx shared memory\n");
- goto out;
- }
-
- size = resource_size(&res);
+ channel->req.shmem = setup_shmem_iomap(cinfo, dev, true, NULL);
+ if (IS_ERR(channel->req.shmem))
+ return PTR_ERR(channel->req.shmem);

- channel->req.shmem = devm_ioremap(dev, res.start, size);
- if (!channel->req.shmem) {
- dev_err(dev, "Failed to ioremap SCMI Tx shared memory\n");
- ret = -EADDRNOTAVAIL;
- goto out;
- }
-
- ret = 0;
-
-out:
- of_node_put(np);
-
- return ret;
+ return 0;
}

static int setup_shmem(struct device *dev, struct scmi_chan_info *cinfo,
diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index b74e5a740f2c..06f68ee0e9f8 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -7,6 +7,8 @@

#include <linux/ktime.h>
#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/processor.h>
#include <linux/types.h>

@@ -133,3 +135,42 @@ bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem)
{
return ioread32(&shmem->flags) & SCMI_SHMEM_FLAG_INTR_ENABLED;
}
+
+void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo,
+ struct device *dev, bool tx,
+ struct resource *res)
+{
+ struct device_node *shmem __free(device_node);
+ const char *desc = tx ? "Tx" : "Rx";
+ int ret, idx = tx ? 0 : 1;
+ struct device *cdev = cinfo->dev;
+ struct resource lres = {};
+ resource_size_t size;
+ void __iomem *addr;
+
+ shmem = of_parse_phandle(cdev->of_node, "shmem", idx);
+ if (!shmem)
+ return ERR_PTR(-ENODEV);
+
+ if (!of_device_is_compatible(shmem, "arm,scmi-shmem"))
+ return ERR_PTR(-ENXIO);
+
+ /* Use a local on-stack as a working area when not provided */
+ if (!res)
+ res = &lres;
+
+ ret = of_address_to_resource(shmem, 0, res);
+ if (ret) {
+ dev_err(cdev, "failed to get SCMI %s shared memory\n", desc);
+ return ERR_PTR(ret);
+ }
+
+ size = resource_size(res);
+ addr = devm_ioremap(dev, res->start, size);
+ if (!addr) {
+ dev_err(dev, "failed to ioremap SCMI %s shared memory\n", desc);
+ return ERR_PTR(-EADDRNOTAVAIL);
+ }
+
+ return addr;
+}
diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c
index 39936e1dd30e..59b6c04b52bc 100644
--- a/drivers/firmware/arm_scmi/smc.c
+++ b/drivers/firmware/arm_scmi/smc.c
@@ -130,9 +130,7 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
struct device *cdev = cinfo->dev;
unsigned long cap_id = ULONG_MAX;
struct scmi_smc *scmi_info;
- resource_size_t size;
- struct resource res;
- struct device_node *np;
+ struct resource res = {};
u32 func_id;
int ret;

@@ -143,31 +141,16 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
if (!scmi_info)
return -ENOMEM;

- np = of_parse_phandle(cdev->of_node, "shmem", 0);
- if (!of_device_is_compatible(np, "arm,scmi-shmem")) {
- of_node_put(np);
- return -ENXIO;
- }
-
- ret = of_address_to_resource(np, 0, &res);
- of_node_put(np);
- if (ret) {
- dev_err(cdev, "failed to get SCMI Tx shared memory\n");
- return ret;
- }
-
- size = resource_size(&res);
- scmi_info->shmem = devm_ioremap(dev, res.start, size);
- if (!scmi_info->shmem) {
- dev_err(dev, "failed to ioremap SCMI Tx shared memory\n");
- return -EADDRNOTAVAIL;
- }
+ scmi_info->shmem = setup_shmem_iomap(cinfo, dev, tx, &res);
+ if (IS_ERR(scmi_info->shmem))
+ return PTR_ERR(scmi_info->shmem);

ret = of_property_read_u32(dev->of_node, "arm,smc-id", &func_id);
if (ret < 0)
return ret;

if (of_device_is_compatible(dev->of_node, "qcom,scmi-smc")) {
+ resource_size_t size = resource_size(&res);
void __iomem *ptr = (void __iomem *)scmi_info->shmem + size - 8;
/* The capability-id is kept in last 8 bytes of shmem.
* +-------+ <-- 0
--
2.45.2