[Dell S5232F, Z9264F] Harden FPGA driver kernel module

For Dell S5232F and Z9264F platforms, be more strict when checking state in ISR of FPGA driver, to harden against spurious interrupts. Signed-off-by: Howard Persh <Howard_Persh@dell.com>
project-arlo · Aug 16, 2019 · bdba462 · bdba462
1 parent 1e45d9f
commit bdba462
Show file tree

Hide file tree

Showing 2 changed files with 14 additions and 4 deletions.
diff --git a/platform/broadcom/sonic-platform-modules-dell/s5232f/modules/dell_s5232f_fpga_ocores.c b/platform/broadcom/sonic-platform-modules-dell/s5232f/modules/dell_s5232f_fpga_ocores.c
@@ -653,15 +653,20 @@ static void fpgai2c_process(struct fpgalogic_i2c *i2c)
         }
     }
 
-    if (i2c->state == STATE_READ) {
+    switch (i2c->state) {
+    case STATE_READ:
         PRINT("fpgai2c_poll STATE_READ i2c->pos=%d msg->len-1 = 0x%x set FPGAI2C_REG_CMD = 0x%x\n",i2c->pos, msg->len-1,
                 i2c->pos == (msg->len-1) ?  FPGAI2C_REG_CMD_READ_NACK : FPGAI2C_REG_CMD_READ_ACK);
         fpgai2c_reg_set(i2c, FPGAI2C_REG_CMD, i2c->pos == (msg->len-1) ?
                 FPGAI2C_REG_CMD_READ_NACK : FPGAI2C_REG_CMD_READ_ACK);
-    } else {
+        break;
+    case STATE_WRITE:
         PRINT("fpgai2c_process set FPGAI2C_REG_DATA(0x%x)\n",FPGAI2C_REG_DATA);
         fpgai2c_reg_set(i2c, FPGAI2C_REG_DATA, msg->buf[i2c->pos++]);
         fpgai2c_reg_set(i2c, FPGAI2C_REG_CMD, FPGAI2C_REG_CMD_WRITE);
+        break;
+    default:
+        printk("Unexpected state, %s:%u state=%d\n", __FILE__, __LINE__, i2c->state);
     }
 }
 

diff --git a/platform/broadcom/sonic-platform-modules-dell/z9264f/modules/dell_z9264f_fpga_ocores.c b/platform/broadcom/sonic-platform-modules-dell/z9264f/modules/dell_z9264f_fpga_ocores.c
@@ -654,15 +654,20 @@ static void fpgai2c_process(struct fpgalogic_i2c *i2c)
         }
     }
 
-    if (i2c->state == STATE_READ) {
+    switch (i2c->state) {
+    case STATE_READ:
         PRINT("fpgai2c_poll STATE_READ i2c->pos=%d msg->len-1 = 0x%x set FPGAI2C_REG_CMD = 0x%x\n",i2c->pos, msg->len-1,
                 i2c->pos == (msg->len-1) ?  FPGAI2C_REG_CMD_READ_NACK : FPGAI2C_REG_CMD_READ_ACK);
         fpgai2c_reg_set(i2c, FPGAI2C_REG_CMD, i2c->pos == (msg->len-1) ?
                 FPGAI2C_REG_CMD_READ_NACK : FPGAI2C_REG_CMD_READ_ACK);
-    } else {
+        break;
+    case STATE_WRITE:
         PRINT("fpgai2c_process set FPGAI2C_REG_DATA(0x%x)\n",FPGAI2C_REG_DATA);
         fpgai2c_reg_set(i2c, FPGAI2C_REG_DATA, msg->buf[i2c->pos++]);
         fpgai2c_reg_set(i2c, FPGAI2C_REG_CMD, FPGAI2C_REG_CMD_WRITE);
+        break;
+    default:
+        printk("Unexpected state, %s:%u state=%d\n", __FILE__, __LINE__, i2c->state);
     }
 }