SMSC LAN9311i - Manual (Page 22)

Two Port 10/100 Managed Ethernet Switch with 16-Bit Non-PCI CPU Interface
Datasheet
Revision 1.4 (08-19-08) 22 SMSC LAN9311/LAN9311i
DATASHEET
2.2.1 System Clocks/Reset/PME Controller
A clock module contained within the LAN9311/LAN9311i generates all the system clocks required by
the device. This module interfaces directly with the external 25MHz crystal/oscillator to generate the
required clock divisions for each internal module, with the exception of the 1588 clocks, which are
generated in the 1588 Time Stamp Clock/Events module. A 16-bit general purpose timer and 32-bit
free-running clock are provided by this module for general purpose use.
The LAN9311/LAN9311i reset events are categorized as chip-level resets, multi-module resets, and
single-module resets.
A chip-level reset is initiated by assertion of any of the following input events:
„ Power-On Reset
„ nRST Pin Reset
A multi-module reset is initiated by assertion of the following:
„ Digital Reset - DIGITAL_RST (bit 0) in the Reset Control Register (RESET_CTL)
- Resets all LAN9311/LAN9311i sub-modules except the Ethernet PHYs (Port 1 PHY, Port 2 PHY,
and Virtual PHY)
„ Soft Reset - SRST (bit 0) in the Hardware Configuration Register (HW_CFG)
- Resets the HBI, Host MAC, and System CSRs below address 100h
A single-module reset is initiated by assertion of the following:
„ Port 2 PHY Reset - PHY2_RST (bit 2) in the Reset Control Register (RESET_CTL) or Reset (bit
15) in the Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x)
- Resets the Port 2 PHY
„ Port 1 PHY Reset - PHY1_RST (bit 1) in the Reset Control Register (RESET_CTL) or Reset (bit
15) in the Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x)
- Resets the Port 1 PHY
„ Virtual PHY Reset - VPHY_RST (bit 0) in the Reset Control Register (RESET_CTL) , (bit 10) in
the Power Management Control Register (PMT_CTRL) , or Reset (bit 15) in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL)
- Resets the Virtual PHY
The LAN9311/LAN9311i supports numerous power management and wakeup features. The Port 1 &
2 PHYs provide general power-down and energy detect power-down modes, which allow a reduction
in PHY power consumption. The Host MAC provides wake-up frame detection and magic packet
detection modes. The LAN9311/LAN9311i can be programmed to issue an external wake signal (PME)
via several methods, including wake on LAN, wake on link status change (energy detect), and magic
packet wakeup. The PME signal is ideal for triggering system power-up using remote Ethernet wakeup
events.
2.2.2 System Interrupt Controller
The LAN9311/LAN9311i provides a multi-tier programmable interrupt structure which is controlled by
the System Interrupt Controller. At the top level are the
Interrupt Status Register (INT_STS) and
Interrupt Enable Register (INT_EN) . These registers aggregate and control all interrupts from the
various LAN9311/LAN9311i sub-modules. The LAN9311/LAN9311i is capable of generating interrupt
events from the following:
„ 1588 Time Stamp
„ Switch Fabric
„ Ethernet PHYs
„ GPIOs
„ Host MAC (FIFOs, power management)