Kernel/Storage: Add support for non-bus mastering IDE controllers

Although unlikely to happen, a user can have an IDE controller that
doesn't support bus master capability. If that's the case, we need to
check for this, and create an IDEChannel (not BMIDEChannel) to allow
IO operations with the controller.

1 files changed, 4 insertions, 8 deletions

diff --git a/Kernel/Storage/IDEChannel.cpp b/Kernel/Storage/IDEChannel.cpp
index 1fc4b9e36c..0ddbb787ea 100644
--- a/Kernel/Storage/IDEChannel.cpp
+++ b/Kernel/Storage/IDEChannel.cpp
@@ -71,7 +71,10 @@ UNMAP_AFTER_INIT IDEChannel::IDEChannel(const IDEController& controller, IOAddre
 
     dbgln_if(PATA_DEBUG, "IDEChannel: {} IO base: {}", channel_type_string(), m_io_group.io_base());
     dbgln_if(PATA_DEBUG, "IDEChannel: {} control base: {}", channel_type_string(), m_io_group.control_base());
-    dbgln_if(PATA_DEBUG, "IDEChannel: {} bus master base: {}", channel_type_string(), m_io_group.bus_master_base());
+    if (m_io_group.bus_master_base().has_value())
+        dbgln_if(PATA_DEBUG, "IDEChannel: {} bus master base: {}", channel_type_string(), m_io_group.bus_master_base().value());
+    else
+        dbgln_if(PATA_DEBUG, "IDEChannel: {} bus master base disabled", channel_type_string());
     m_parent_controller->enable_pin_based_interrupts();
 
     detect_disks();
@@ -181,13 +184,6 @@ void IDEChannel::handle_irq(const RegisterState&)
 
     m_entropy_source.add_random_event(status);
 
-    u8 bstatus = m_io_group.bus_master_base().offset(2).in<u8>();
-    if (!(bstatus & 0x4)) {
-        // interrupt not from this device, ignore
-        dbgln_if(PATA_DEBUG, "IDEChannel: ignore interrupt");
-        return;
-    }
-
     ScopedSpinLock lock(m_request_lock);
     dbgln_if(PATA_DEBUG, "IDEChannel: interrupt: DRQ={}, BSY={}, DRDY={}",
         (status & ATA_SR_DRQ) != 0,