Some shared memory areas might only support a certain access width,
such as 32-bit, which memcpy_{from,to}_io() does not adhere to at least
on ARM64 by making both 8-bit and 64-bit accesses to such memory.
Update the shmem layer to support reading from and writing to such
shared memory area using the specified I/O width in the Device Tree. The
various transport layers making use of the shmem.c code are updated
accordingly to pass the I/O accessors that they store.
Signed-off-by: Florian Fainelli <florian.fainelli@xxxxxxxxxxxx>
---
drivers/firmware/arm_scmi/common.h | 32 ++++++-
.../arm_scmi/scmi_transport_mailbox.c | 13 ++-
.../firmware/arm_scmi/scmi_transport_optee.c | 11 ++-
.../firmware/arm_scmi/scmi_transport_smc.c | 11 ++-
drivers/firmware/arm_scmi/shmem.c | 86 +++++++++++++++++--
5 files changed, 132 insertions(+), 21 deletions(-)
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 69928bbd01c2..73bb496fac01 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -316,6 +316,26 @@ enum scmi_bad_msg {
MSG_MBOX_SPURIOUS = -5,
};
+/* Used for compactness and signature validation of the function pointers being
+ * passed.
+ */
+typedef void (*shmem_copy_toio_t)(volatile void __iomem *to, const void *from,
+ size_t count);
+typedef void (*shmem_copy_fromio_t)(void *to, const volatile void __iomem *from,
+ size_t count);
+
+/**
+ * struct scmi_shmem_io_ops - I/O operations to read from/write to
+ * Shared Memory
+ *
+ * @toio: Copy data to the shared memory area
+ * @fromio: Copy data from the shared memory area
+ */
+struct scmi_shmem_io_ops {
+ shmem_copy_fromio_t fromio;
+ shmem_copy_toio_t toio;
+};
+
/* shmem related declarations */
struct scmi_shared_mem;
@@ -336,13 +356,16 @@ struct scmi_shared_mem;
struct scmi_shared_mem_operations {
void (*tx_prepare)(struct scmi_shared_mem __iomem *shmem,
struct scmi_xfer *xfer,
- struct scmi_chan_info *cinfo);
+ struct scmi_chan_info *cinfo,
+ shmem_copy_toio_t toio);
u32 (*read_header)(struct scmi_shared_mem __iomem *shmem);
void (*fetch_response)(struct scmi_shared_mem __iomem *shmem,
- struct scmi_xfer *xfer);
+ struct scmi_xfer *xfer,
+ shmem_copy_fromio_t fromio);
void (*fetch_notification)(struct scmi_shared_mem __iomem *shmem,
- size_t max_len, struct scmi_xfer *xfer);
+ size_t max_len, struct scmi_xfer *xfer,
+ shmem_copy_fromio_t fromio);
void (*clear_channel)(struct scmi_shared_mem __iomem *shmem);
bool (*poll_done)(struct scmi_shared_mem __iomem *shmem,
struct scmi_xfer *xfer);
@@ -350,7 +373,8 @@ struct scmi_shared_mem_operations {
bool (*channel_intr_enabled)(struct scmi_shared_mem __iomem *shmem);
void __iomem *(*setup_iomap)(struct scmi_chan_info *cinfo,
struct device *dev,
- bool tx, struct resource *res);
+ bool tx, struct resource *res,
+ struct scmi_shmem_io_ops **ops);
};
const struct scmi_shared_mem_operations *scmi_shared_mem_operations_get(void);
diff --git a/drivers/firmware/arm_scmi/scmi_transport_mailbox.c b/drivers/firmware/arm_scmi/scmi_transport_mailbox.c
index dc5ca894d5eb..1a2e90e5c765 100644
--- a/drivers/firmware/arm_scmi/scmi_transport_mailbox.c
+++ b/drivers/firmware/arm_scmi/scmi_transport_mailbox.c
@@ -25,6 +25,7 @@
* @chan_platform_receiver: Optional Platform Receiver mailbox unidirectional channel
* @cinfo: SCMI channel info
* @shmem: Transmit/Receive shared memory area
+ * @io_ops: Transport specific I/O operations
*/
struct scmi_mailbox {
struct mbox_client cl;
@@ -33,6 +34,7 @@ struct scmi_mailbox {
struct mbox_chan *chan_platform_receiver;
struct scmi_chan_info *cinfo;
struct scmi_shared_mem __iomem *shmem;
+ struct scmi_shmem_io_ops *io_ops;
};
#define client_to_scmi_mailbox(c) container_of(c, struct scmi_mailbox, cl)
@@ -43,7 +45,8 @@ static void tx_prepare(struct mbox_client *cl, void *m)
{
struct scmi_mailbox *smbox = client_to_scmi_mailbox(cl);
- core->shmem->tx_prepare(smbox->shmem, m, smbox->cinfo);
+ core->shmem->tx_prepare(smbox->shmem, m, smbox->cinfo,
+ smbox->io_ops->toio);
}
static void rx_callback(struct mbox_client *cl, void *m)
@@ -197,7 +200,8 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
if (!smbox)
return -ENOMEM;
- smbox->shmem = core->shmem->setup_iomap(cinfo, dev, tx, NULL);
+ smbox->shmem = core->shmem->setup_iomap(cinfo, dev, tx, NULL,
+ &smbox->io_ops);
if (IS_ERR(smbox->shmem))
return PTR_ERR(smbox->shmem);
@@ -298,7 +302,7 @@ static void mailbox_fetch_response(struct scmi_chan_info *cinfo,
{
struct scmi_mailbox *smbox = cinfo->transport_info;
- core->shmem->fetch_response(smbox->shmem, xfer);
+ core->shmem->fetch_response(smbox->shmem, xfer, smbox->io_ops->fromio);
}
static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
@@ -306,7 +310,8 @@ static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
{
struct scmi_mailbox *smbox = cinfo->transport_info;
- core->shmem->fetch_notification(smbox->shmem, max_len, xfer);
+ core->shmem->fetch_notification(smbox->shmem, max_len, xfer,
+ smbox->io_ops->fromio);
}
static void mailbox_clear_channel(struct scmi_chan_info *cinfo)
diff --git a/drivers/firmware/arm_scmi/scmi_transport_optee.c b/drivers/firmware/arm_scmi/scmi_transport_optee.c
index 08911f40d1ff..2be4124c6826 100644
--- a/drivers/firmware/arm_scmi/scmi_transport_optee.c
+++ b/drivers/firmware/arm_scmi/scmi_transport_optee.c
@@ -114,6 +114,7 @@ enum scmi_optee_pta_cmd {
* @req.shmem: Virtual base address of the shared memory
* @req.msg: Shared memory protocol handle for SCMI request and
* synchronous response
+ * @io_ops: Transport specific I/O operations
* @tee_shm: TEE shared memory handle @req or NULL if using IOMEM shmem
* @link: Reference in agent's channel list
*/
@@ -128,6 +129,7 @@ struct scmi_optee_channel {
struct scmi_shared_mem __iomem *shmem;
struct scmi_msg_payld *msg;
} req;
+ struct scmi_shmem_io_ops *io_ops;
struct tee_shm *tee_shm;
struct list_head link;
};
@@ -350,7 +352,8 @@ 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)
{
- channel->req.shmem = core->shmem->setup_iomap(cinfo, dev, true, NULL);
+ channel->req.shmem = core->shmem->setup_iomap(cinfo, dev, true, NULL,
+ &channel->io_ops);
if (IS_ERR(channel->req.shmem))
return PTR_ERR(channel->req.shmem);
@@ -465,7 +468,8 @@ static int scmi_optee_send_message(struct scmi_chan_info *cinfo,
ret = invoke_process_msg_channel(channel,
core->msg->command_size(xfer));
} else {
- core->shmem->tx_prepare(channel->req.shmem, xfer, cinfo);
+ core->shmem->tx_prepare(channel->req.shmem, xfer, cinfo,
+ channel->io_ops->toio);
ret = invoke_process_smt_channel(channel);
}
@@ -484,7 +488,8 @@ static void scmi_optee_fetch_response(struct scmi_chan_info *cinfo,
core->msg->fetch_response(channel->req.msg,
channel->rx_len, xfer);
else
- core->shmem->fetch_response(channel->req.shmem, xfer);
+ core->shmem->fetch_response(channel->req.shmem, xfer,
+ channel->io_ops->fromio);
}
static void scmi_optee_mark_txdone(struct scmi_chan_info *cinfo, int ret,
diff --git a/drivers/firmware/arm_scmi/scmi_transport_smc.c b/drivers/firmware/arm_scmi/scmi_transport_smc.c
index c6c69a17a9cc..04e715ec1570 100644
--- a/drivers/firmware/arm_scmi/scmi_transport_smc.c
+++ b/drivers/firmware/arm_scmi/scmi_transport_smc.c
@@ -45,6 +45,7 @@
* @irq: An optional IRQ for completion
* @cinfo: SCMI channel info
* @shmem: Transmit/Receive shared memory area
+ * @io_ops: Transport specific I/O operations
* @shmem_lock: Lock to protect access to Tx/Rx shared memory area.
* Used when NOT operating in atomic mode.
* @inflight: Atomic flag to protect access to Tx/Rx shared memory area.
@@ -60,6 +61,7 @@ struct scmi_smc {
int irq;
struct scmi_chan_info *cinfo;
struct scmi_shared_mem __iomem *shmem;
+ struct scmi_shmem_io_ops *io_ops;
/* Protect access to shmem area */
struct mutex shmem_lock;
#define INFLIGHT_NONE MSG_TOKEN_MAX
@@ -144,7 +146,8 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
if (!scmi_info)
return -ENOMEM;
- scmi_info->shmem = core->shmem->setup_iomap(cinfo, dev, tx, &res);
+ scmi_info->shmem = core->shmem->setup_iomap(cinfo, dev, tx, &res,
+ &scmi_info->io_ops);
if (IS_ERR(scmi_info->shmem))
return PTR_ERR(scmi_info->shmem);
@@ -229,7 +232,8 @@ static int smc_send_message(struct scmi_chan_info *cinfo,
*/
smc_channel_lock_acquire(scmi_info, xfer);
- core->shmem->tx_prepare(scmi_info->shmem, xfer, cinfo);
+ core->shmem->tx_prepare(scmi_info->shmem, xfer, cinfo,
+ scmi_info->io_ops->toio);
if (scmi_info->cap_id != ULONG_MAX)
arm_smccc_1_1_invoke(scmi_info->func_id, scmi_info->cap_id, 0,
@@ -253,7 +257,8 @@ static void smc_fetch_response(struct scmi_chan_info *cinfo,
{
struct scmi_smc *scmi_info = cinfo->transport_info;
- core->shmem->fetch_response(scmi_info->shmem, xfer);
+ core->shmem->fetch_response(scmi_info->shmem, xfer,
+ scmi_info->io_ops->fromio);
}
static void smc_mark_txdone(struct scmi_chan_info *cinfo, int ret,
diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index 01d8a9398fe8..aded5f1cd49f 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -34,9 +34,67 @@ struct scmi_shared_mem {
u8 msg_payload[];
};
+static inline void shmem_memcpy_fromio32(void *to,
+ const volatile void __iomem *from,
+ size_t count)
+{
+ while (count) {
+ *(u32 *)to = __raw_readl(from);
+ from += 4;
+ to += 4;
+ count -= 4;
+ }
+
+ /* Ensure all reads from I/O have completed */
+ rmb();
+}
+
+static inline void shmem_memcpy_toio32(volatile void __iomem *to,
+ const void *from,
+ size_t count)
+{
+ while (count) {
+ __raw_writel(*(u32 *)from, to);
+ from += 4;
+ to += 4;
+ count -= 4;
+ }
+
+ /* Ensure all writes to I/O have completed */
+ wmb();
+}
+
+static struct scmi_shmem_io_ops shmem_io_ops32 = {
+ .fromio = shmem_memcpy_fromio32,
+ .toio = shmem_memcpy_toio32,
+};
+
+/* Wrappers are needed for proper memcpy_{from,to}_io expansion by the
+ * pre-processor.
+ */
+static inline void shmem_memcpy_fromio(void *to,
+ const volatile void __iomem *from,
+ size_t count)
+{
+ memcpy_fromio(to, from, count);
+}
+
+static inline void shmem_memcpy_toio(volatile void __iomem *to,
+ const void *from,
+ size_t count)
+{
+ memcpy_toio(to, from, count);
+}
+
+static struct scmi_shmem_io_ops shmem_io_ops_default = {
+ .fromio = shmem_memcpy_fromio,
+ .toio = shmem_memcpy_toio,
+};
+
static void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem,
struct scmi_xfer *xfer,
- struct scmi_chan_info *cinfo)
+ struct scmi_chan_info *cinfo,
+ shmem_copy_toio_t copy_toio)
{
ktime_t stop;
@@ -73,7 +131,7 @@ static void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem,
iowrite32(sizeof(shmem->msg_header) + xfer->tx.len, &shmem->length);
iowrite32(pack_scmi_header(&xfer->hdr), &shmem->msg_header);
if (xfer->tx.buf)
- memcpy_toio(shmem->msg_payload, xfer->tx.buf, xfer->tx.len);
+ copy_toio(shmem->msg_payload, xfer->tx.buf, xfer->tx.len);
}
static u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem)
@@ -82,7 +140,8 @@ static u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem)
}
static void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem,
- struct scmi_xfer *xfer)
+ struct scmi_xfer *xfer,
+ shmem_copy_fromio_t copy_fromio)
{
size_t len = ioread32(&shmem->length);
@@ -91,11 +150,12 @@ static void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem,
xfer->rx.len = min_t(size_t, xfer->rx.len, len > 8 ? len - 8 : 0);
/* Take a copy to the rx buffer.. */
- memcpy_fromio(xfer->rx.buf, shmem->msg_payload + 4, xfer->rx.len);
+ copy_fromio(xfer->rx.buf, shmem->msg_payload + 4, xfer->rx.len);
}
static void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem,
- size_t max_len, struct scmi_xfer *xfer)
+ size_t max_len, struct scmi_xfer *xfer,
+ shmem_copy_fromio_t copy_fromio)
{
size_t len = ioread32(&shmem->length);
@@ -103,7 +163,7 @@ static void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem,
xfer->rx.len = min_t(size_t, max_len, len > 4 ? len - 4 : 0);
/* Take a copy to the rx buffer.. */
- memcpy_fromio(xfer->rx.buf, shmem->msg_payload, xfer->rx.len);
+ copy_fromio(xfer->rx.buf, shmem->msg_payload, xfer->rx.len);
}
static void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem)
@@ -139,7 +199,8 @@ static bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem)
static void __iomem *shmem_setup_iomap(struct scmi_chan_info *cinfo,
struct device *dev, bool tx,
- struct resource *res)
+ struct resource *res,
+ struct scmi_shmem_io_ops **ops)
{
struct device_node *shmem __free(device_node);
const char *desc = tx ? "Tx" : "Rx";
@@ -148,6 +209,7 @@ static void __iomem *shmem_setup_iomap(struct scmi_chan_info *cinfo,
struct resource lres = {};
resource_size_t size;
void __iomem *addr;
+ u32 reg_io_width;
shmem = of_parse_phandle(cdev->of_node, "shmem", idx);
if (!shmem)
@@ -173,6 +235,16 @@ static void __iomem *shmem_setup_iomap(struct scmi_chan_info *cinfo,
return IOMEM_ERR_PTR(-EADDRNOTAVAIL);
}
+ of_property_read_u32(shmem, "reg-io-width", ®_io_width);
+ switch (reg_io_width) {
+ case 4:
+ *ops = &shmem_io_ops32;
+ break;
+ default:
+ *ops = &shmem_io_ops_default;
+ break;
+ }
+
return addr;
}
--
2.34.1
