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Diffstat (limited to 'meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0100-Mailbox-Enabling-interrupt-based-mailbox.patch')
-rw-r--r--meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0100-Mailbox-Enabling-interrupt-based-mailbox.patch234
1 files changed, 234 insertions, 0 deletions
diff --git a/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0100-Mailbox-Enabling-interrupt-based-mailbox.patch b/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0100-Mailbox-Enabling-interrupt-based-mailbox.patch
new file mode 100644
index 000000000..e67adb729
--- /dev/null
+++ b/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0100-Mailbox-Enabling-interrupt-based-mailbox.patch
@@ -0,0 +1,234 @@
+From 7094f4d8efea8e059c965ba70c73d5226af392cb Mon Sep 17 00:00:00 2001
+From: "Arun P. Mohanan" <arun.p.m@linux.intel.com>
+Date: Wed, 11 Mar 2020 17:23:49 +0530
+Subject: [PATCH] [Mailbox] Enabling interrupt based mailbox
+
+Modifying the mailbox driver to use FIFO queue while using interrupt.
+
+Signed-off-by: Arun P. Mohanan <arun.p.m@linux.intel.com>
+---
+ drivers/soc/aspeed/aspeed-lpc-mbox.c | 101 ++++++++++++++++++---------
+ 1 file changed, 68 insertions(+), 33 deletions(-)
+
+diff --git a/drivers/soc/aspeed/aspeed-lpc-mbox.c b/drivers/soc/aspeed/aspeed-lpc-mbox.c
+index 795107206022..99f38a4e4550 100644
+--- a/drivers/soc/aspeed/aspeed-lpc-mbox.c
++++ b/drivers/soc/aspeed/aspeed-lpc-mbox.c
+@@ -12,10 +12,11 @@
+ #include <linux/poll.h>
+ #include <linux/regmap.h>
+ #include <linux/slab.h>
++#include <linux/kfifo.h>
+
+ #define DEVICE_NAME "aspeed-mbox"
+
+-#define MBX_USE_INTERRUPT 0
++#define MBX_USE_INTERRUPT 1
+
+ #define ASPEED_MBOX_NUM_REGS 16
+
+@@ -29,6 +30,7 @@
+ #define ASPEED_MBOX_HOST_CTRL 0x4c
+ #define ASPEED_MBOX_INTERRUPT_0 0x50
+ #define ASPEED_MBOX_INTERRUPT_1 0x54
++#define MBOX_FIFO_SIZE 64
+
+ struct aspeed_mbox {
+ struct miscdevice miscdev;
+@@ -38,6 +40,8 @@ struct aspeed_mbox {
+ int irq;
+ wait_queue_head_t queue;
+ struct mutex mutex;
++ struct kfifo fifo;
++ spinlock_t lock;
+ };
+
+ static atomic_t aspeed_mbox_open_count = ATOMIC_INIT(0);
+@@ -74,20 +78,37 @@ static struct aspeed_mbox *file_mbox(struct file *file)
+ return container_of(file->private_data, struct aspeed_mbox, miscdev);
+ }
+
++/* Save a byte to a FIFO and discard the oldest byte if FIFO is full */
++static void put_fifo_with_discard(struct aspeed_mbox *mbox, u8 val)
++{
++ if (!kfifo_initialized(&mbox->fifo))
++ return;
++ if (kfifo_is_full(&mbox->fifo))
++ kfifo_skip(&mbox->fifo);
++ kfifo_put(&mbox->fifo, val);
++}
++
+ static int aspeed_mbox_open(struct inode *inode, struct file *file)
+ {
+ #if MBX_USE_INTERRUPT
+ struct aspeed_mbox *mbox = file_mbox(file);
++ int i;
+ #endif
+
+ if (atomic_inc_return(&aspeed_mbox_open_count) == 1) {
+ #if MBX_USE_INTERRUPT
+ /*
+- * Clear the interrupt status bit if it was left on and unmask
+- * interrupts.
+- * ASPEED_MBOX_CTRL_RECV bit is W1C, this also unmasks in 1 step
++ * Reset the FIFO while opening to clear the old cached data
++ * and load the FIFO with latest mailbox register values.
+ */
+- aspeed_mbox_outb(mbox, ASPEED_MBOX_CTRL_RECV, ASPEED_MBOX_BMC_CTRL);
++ kfifo_reset(&mbox->fifo);
++ spin_lock_irq(&mbox->lock);
++ for (i = 0; i < ASPEED_MBOX_NUM_REGS; i++) {
++ put_fifo_with_discard(mbox,
++ aspeed_mbox_inb(mbox, ASPEED_MBOX_DATA_0 + (i * 4)));
++ }
++ spin_unlock_irq(&mbox->lock);
++
+ #endif
+ return 0;
+ }
+@@ -102,6 +123,8 @@ static ssize_t aspeed_mbox_read(struct file *file, char __user *buf,
+ struct aspeed_mbox *mbox = file_mbox(file);
+ char __user *p = buf;
+ ssize_t ret;
++ unsigned int copied;
++ unsigned long flags;
+ int i;
+
+ if (!access_ok(buf, count))
+@@ -111,15 +134,29 @@ static ssize_t aspeed_mbox_read(struct file *file, char __user *buf,
+ return -EINVAL;
+
+ #if MBX_USE_INTERRUPT
+- if (file->f_flags & O_NONBLOCK) {
+- if (!(aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL) &
+- ASPEED_MBOX_CTRL_RECV))
++ /*
++ * Restrict count as per the number of mailbox registers
++ * if interrupt is enabled.
++ */
++ if (count != ASPEED_MBOX_NUM_REGS)
++ return -EINVAL;
++
++ if (kfifo_is_empty(&mbox->fifo)) {
++ if (file->f_flags & O_NONBLOCK){
+ return -EAGAIN;
+- } else if (wait_event_interruptible(mbox->queue,
+- aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL) &
+- ASPEED_MBOX_CTRL_RECV)) {
+- return -ERESTARTSYS;
++ }
++ ret = wait_event_interruptible(mbox->queue,
++ !kfifo_is_empty(&mbox->fifo));
++ if (ret == -ERESTARTSYS){
++ return -EINTR;
++ }
+ }
++
++ spin_lock_irqsave(&mbox->lock, flags);
++ ret = kfifo_to_user(&mbox->fifo, buf, count, &copied);
++ spin_unlock_irqrestore(&mbox->lock, flags);
++ return ret ? ret : copied;
++
+ #endif
+
+ mutex_lock(&mbox->mutex);
+@@ -134,11 +171,6 @@ static ssize_t aspeed_mbox_read(struct file *file, char __user *buf,
+ p++;
+ count--;
+ }
+-
+-#if MBX_USE_INTERRUPT
+- /* ASPEED_MBOX_CTRL_RECV bit is write to clear, this also unmasks in 1 step */
+- aspeed_mbox_outb(mbox, ASPEED_MBOX_CTRL_RECV, ASPEED_MBOX_BMC_CTRL);
+-#endif
+ ret = p - buf;
+
+ out_unlock:
+@@ -186,16 +218,9 @@ static ssize_t aspeed_mbox_write(struct file *file, const char __user *buf,
+ static unsigned int aspeed_mbox_poll(struct file *file, poll_table *wait)
+ {
+ struct aspeed_mbox *mbox = file_mbox(file);
+- unsigned int mask = 0;
+
+ poll_wait(file, &mbox->queue, wait);
+-
+-#if MBX_USE_INTERRUPT
+- if (aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL) & ASPEED_MBOX_CTRL_RECV)
+-#endif
+- mask |= POLLIN;
+-
+- return mask;
++ return !kfifo_is_empty(&mbox->fifo) ? POLLIN : 0;
+ }
+
+ static int aspeed_mbox_release(struct inode *inode, struct file *file)
+@@ -220,19 +245,23 @@ static irqreturn_t aspeed_mbox_irq(int irq, void *arg)
+ #if MBX_USE_INTERRUPT
+ int i;
+
+-// if (!(aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL) & ASPEED_MBOX_CTRL_RECV))
+-// return IRQ_NONE;
+-
+- printk(KERN_ERR "BMC_CTRL: 0x%02x\n",
++ dev_dbg(mbox->miscdev.parent, "BMC_CTRL11: 0x%02x\n",
+ aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL));
+- printk(KERN_ERR "STATUS_0: 0x%02x\n",
++ dev_dbg(mbox->miscdev.parent, "STATUS_0: 0x%02x\n",
+ aspeed_mbox_inb(mbox, ASPEED_MBOX_STATUS_0));
+- printk(KERN_ERR "STATUS_1: 0x%02x\n",
++ dev_dbg(mbox->miscdev.parent, "STATUS_1: 0x%02x\n",
+ aspeed_mbox_inb(mbox, ASPEED_MBOX_STATUS_1));
+ for (i = 0; i < ASPEED_MBOX_NUM_REGS; i++) {
+- printk(KERN_ERR "DATA_%d: 0x%02x\n", i,
++ dev_dbg(mbox->miscdev.parent, "DATA_%d: 0x%02x\n", i,
+ aspeed_mbox_inb(mbox, ASPEED_MBOX_DATA_0 + (i * 4)));
+ }
++
++ spin_lock(&mbox->lock);
++ for (i = 0; i < ASPEED_MBOX_NUM_REGS; i++) {
++ put_fifo_with_discard(mbox,
++ aspeed_mbox_inb(mbox, ASPEED_MBOX_DATA_0 + (i * 4)));
++ }
++ spin_unlock(&mbox->lock);
+ #endif
+
+ /* Clear interrupt status */
+@@ -249,7 +278,6 @@ static int aspeed_mbox_config_irq(struct aspeed_mbox *mbox,
+ {
+ struct device *dev = &pdev->dev;
+ int rc;
+-
+ mbox->irq = platform_get_irq(pdev, 0);
+ if (!mbox->irq)
+ return -ENODEV;
+@@ -300,6 +328,7 @@ static int aspeed_mbox_probe(struct platform_device *pdev)
+ return -ENODEV;
+ }
+
++ spin_lock_init(&mbox->lock);
+ mutex_init(&mbox->mutex);
+ init_waitqueue_head(&mbox->queue);
+
+@@ -316,6 +345,11 @@ static int aspeed_mbox_probe(struct platform_device *pdev)
+ return rc;
+ }
+
++ /* Create FIFO data structure */
++ rc = kfifo_alloc(&mbox->fifo, MBOX_FIFO_SIZE, GFP_KERNEL);
++ if (rc)
++ return rc;
++
+ mbox->miscdev.minor = MISC_DYNAMIC_MINOR;
+ mbox->miscdev.name = DEVICE_NAME;
+ mbox->miscdev.fops = &aspeed_mbox_fops;
+@@ -349,6 +383,7 @@ static int aspeed_mbox_remove(struct platform_device *pdev)
+
+ misc_deregister(&mbox->miscdev);
+ clk_disable_unprepare(mbox->clk);
++ kfifo_free(&mbox->fifo);
+
+ return 0;
+ }
+--
+2.17.1
+
generated by cgit v1.2.3 (git 2.39.0) at 2024-06-16 07:46:57 +0300