linux-sg2042/Documentation/devicetree/bindings/net/marvell-armada-370-neta.txt

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net: mvneta: Add network support for Armada 3700 SoC Armada 3700 is a new ARMv8 SoC from Marvell using same network controller as older Armada 370/38x/XP. There are however some differences that needed taking into account when adding support for it: * open default MBUS window to 4GB of DRAM - Armada 3700 SoC's Mbus configuration for network controller has to be done on two levels: global and per-port. The first one is inherited from the bootloader. The latter can be opened in a default way, leaving arbitration to the bus controller. Hence filled mbus_dram_target_info structure is not needed * make per-CPU operation optional - Recent patches adding RSS and XPS support for Armada 38x/XP enabled per-CPU operation of the controller by default. Contrary to older SoC's Armada 3700 SoC's network controller is not capable of per-CPU processing due to interrupt lines' connectivity. This patch restores non-per-CPU operation, which is now optional and depends on neta_armada3700 flag value in mvneta_port structure. In order not to complicate the code, separate interrupt subroutine is implemented. For now, on the Armada 3700, RSS is disabled as the current implementation depend on the per cpu interrupts. [gregory.clement@free-electrons.com: extract from a larger patch, replace some ifdef and port to net-next for v4.10] Signed-off-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Tested-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 01:03:09 +08:00
* Marvell Armada 370 / Armada XP / Armada 3700 Ethernet Controller (NETA)
net: mvneta: driver for Marvell Armada 370/XP network unit This patch contains a new network driver for the network unit of the ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B processor, a Marvell-developed ARM core that implements the ARMv7 instruction set. Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery), the network unit in Armada 370 and Armada XP is highly different. This is the reason why this new 'mvneta' driver is needed, while the older ARM Marvell SoCs use the 'mv643xx_eth' driver. Here is an overview of the most important hardware changes that require a new, specific, driver for the network unit of Armada 370/XP: - The new network unit has a completely different design and layout for the RX and TX descriptors. They are now organized as a simple array (each RX and TX queue has base address and size of this array) rather than a linked list as in the old SoCs. - The new network unit has a different RXQ and TXQ management: this management is done using special read/write counter registers, while in the Old SocS, it was done using the Ownership bit in RX and TX descriptors. - The new network unit has different interrupt registers - The new network unit way of cleaning of interrupts is not done by writing to the cause register, but by updating per-queue counters - The new network unit has different GMAC registers (link, speed, duplex configuration) and different WRR registers. - The new network unit has lots of new units like PnC (Parser and Classifier), PMT, BM (Memory Buffer Management), xPON, and more. The driver proposed in the current patch only handles the basic features. Additional hardware features will progressively be supported as needed. This code has originally been written by Rami Rosen <rosenr@marvell.com>, and then reviewed and cleaned up by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-17 19:04:28 +08:00
Required properties:
- compatible: could be one of the following:
net: mvneta: Add network support for Armada 3700 SoC Armada 3700 is a new ARMv8 SoC from Marvell using same network controller as older Armada 370/38x/XP. There are however some differences that needed taking into account when adding support for it: * open default MBUS window to 4GB of DRAM - Armada 3700 SoC's Mbus configuration for network controller has to be done on two levels: global and per-port. The first one is inherited from the bootloader. The latter can be opened in a default way, leaving arbitration to the bus controller. Hence filled mbus_dram_target_info structure is not needed * make per-CPU operation optional - Recent patches adding RSS and XPS support for Armada 38x/XP enabled per-CPU operation of the controller by default. Contrary to older SoC's Armada 3700 SoC's network controller is not capable of per-CPU processing due to interrupt lines' connectivity. This patch restores non-per-CPU operation, which is now optional and depends on neta_armada3700 flag value in mvneta_port structure. In order not to complicate the code, separate interrupt subroutine is implemented. For now, on the Armada 3700, RSS is disabled as the current implementation depend on the per cpu interrupts. [gregory.clement@free-electrons.com: extract from a larger patch, replace some ifdef and port to net-next for v4.10] Signed-off-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Tested-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 01:03:09 +08:00
"marvell,armada-370-neta"
"marvell,armada-xp-neta"
"marvell,armada-3700-neta"
net: mvneta: driver for Marvell Armada 370/XP network unit This patch contains a new network driver for the network unit of the ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B processor, a Marvell-developed ARM core that implements the ARMv7 instruction set. Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery), the network unit in Armada 370 and Armada XP is highly different. This is the reason why this new 'mvneta' driver is needed, while the older ARM Marvell SoCs use the 'mv643xx_eth' driver. Here is an overview of the most important hardware changes that require a new, specific, driver for the network unit of Armada 370/XP: - The new network unit has a completely different design and layout for the RX and TX descriptors. They are now organized as a simple array (each RX and TX queue has base address and size of this array) rather than a linked list as in the old SoCs. - The new network unit has a different RXQ and TXQ management: this management is done using special read/write counter registers, while in the Old SocS, it was done using the Ownership bit in RX and TX descriptors. - The new network unit has different interrupt registers - The new network unit way of cleaning of interrupts is not done by writing to the cause register, but by updating per-queue counters - The new network unit has different GMAC registers (link, speed, duplex configuration) and different WRR registers. - The new network unit has lots of new units like PnC (Parser and Classifier), PMT, BM (Memory Buffer Management), xPON, and more. The driver proposed in the current patch only handles the basic features. Additional hardware features will progressively be supported as needed. This code has originally been written by Rami Rosen <rosenr@marvell.com>, and then reviewed and cleaned up by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-17 19:04:28 +08:00
- reg: address and length of the register set for the device.
- interrupts: interrupt for the device
- phy: See ethernet.txt file in the same directory.
- phy-mode: See ethernet.txt file in the same directory
- clocks: List of clocks for this device. At least one clock is
mandatory for the core clock. If several clocks are given, then the
clock-names property must be used to identify them.
net: mvneta: driver for Marvell Armada 370/XP network unit This patch contains a new network driver for the network unit of the ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B processor, a Marvell-developed ARM core that implements the ARMv7 instruction set. Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery), the network unit in Armada 370 and Armada XP is highly different. This is the reason why this new 'mvneta' driver is needed, while the older ARM Marvell SoCs use the 'mv643xx_eth' driver. Here is an overview of the most important hardware changes that require a new, specific, driver for the network unit of Armada 370/XP: - The new network unit has a completely different design and layout for the RX and TX descriptors. They are now organized as a simple array (each RX and TX queue has base address and size of this array) rather than a linked list as in the old SoCs. - The new network unit has a different RXQ and TXQ management: this management is done using special read/write counter registers, while in the Old SocS, it was done using the Ownership bit in RX and TX descriptors. - The new network unit has different interrupt registers - The new network unit way of cleaning of interrupts is not done by writing to the cause register, but by updating per-queue counters - The new network unit has different GMAC registers (link, speed, duplex configuration) and different WRR registers. - The new network unit has lots of new units like PnC (Parser and Classifier), PMT, BM (Memory Buffer Management), xPON, and more. The driver proposed in the current patch only handles the basic features. Additional hardware features will progressively be supported as needed. This code has originally been written by Rami Rosen <rosenr@marvell.com>, and then reviewed and cleaned up by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-17 19:04:28 +08:00
Optional properties:
- tx-csum-limit: maximum mtu supported by port that allow TX checksum.
Value is presented in bytes. If not used, by default 1600B is set for
"marvell,armada-370-neta" and 9800B for others.
- clock-names: List of names corresponding to clocks property; shall be
"core" for core clock and "bus" for the optional bus clock.
- phys: comphy for the ethernet port, see ../phy/phy-bindings.txt
net: mvneta: bm: add support for hardware buffer management Buffer manager (BM) is a dedicated hardware unit that can be used by all ethernet ports of Armada XP and 38x SoC's. It allows to offload CPU on RX path by sparing DRAM access on refilling buffer pool, hardware-based filling of descriptor ring data and better memory utilization due to HW arbitration for using 'short' pools for small packets. Tests performed with A388 SoC working as a network bridge between two packet generators showed increase of maximum processed 64B packets by ~20k (~555k packets with BM enabled vs ~535 packets without BM). Also when pushing 1500B-packets with a line rate achieved, CPU load decreased from around 25% without BM to 20% with BM. BM comprise up to 4 buffer pointers' (BP) rings kept in DRAM, which are called external BP pools - BPPE. Allocating and releasing buffer pointers (BP) to/from BPPE is performed indirectly by write/read access to a dedicated internal SRAM, where internal BP pools (BPPI) are placed. BM hardware controls status of BPPE automatically, as well as assigning proper buffers to RX descriptors. For more details please refer to Functional Specification of Armada XP or 38x SoC. In order to enable support for a separate hardware block, common for all ports, a new driver has to be implemented ('mvneta_bm'). It provides initialization sequence of address space, clocks, registers, SRAM, empty pools' structures and also obtaining optional configuration from DT (please refer to device tree binding documentation). mvneta_bm exposes also a necessary API to mvneta driver, as well as a dedicated structure with BM information (bm_priv), whose presence is used as a flag notifying of BM usage by port. It has to be ensured that mvneta_bm probe is executed prior to the ones in ports' driver. In case BM is not used or its probe fails, mvneta falls back to use software buffer management. A sequence executed in mvneta_probe function is modified in order to have an access to needed resources before possible port's BM initialization is done. According to port-pools mapping provided by DT appropriate registers are configured and the buffer pools are filled. RX path is modified accordingly. Becaues the hardware allows a wide variety of configuration options, following assumptions are made: * using BM mechanisms can be selectively disabled/enabled basing on DT configuration among the ports * 'long' pool's single buffer size is tied to port's MTU * using 'long' pool by port is obligatory and it cannot be shared * using 'short' pool for smaller packets is optional * one 'short' pool can be shared among all ports This commit enables hardware buffer management operation cooperating with existing mvneta driver. New device tree binding documentation is added and the one of mvneta is updated accordingly. [gregory.clement@free-electrons.com: removed the suspend/resume part] Signed-off-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 16:39:03 +08:00
Optional properties (valid only for Armada XP/38x):
- buffer-manager: a phandle to a buffer manager node. Please refer to
Documentation/devicetree/bindings/net/marvell-neta-bm.txt
- bm,pool-long: ID of a pool, that will accept all packets of a size
higher than 'short' pool's threshold (if set) and up to MTU value.
Obligatory, when the port is supposed to use hardware
buffer management.
- bm,pool-short: ID of a pool, that will be used for accepting
packets of a size lower than given threshold. If not set, the port
will use a single 'long' pool for all packets, as defined above.
net: mvneta: driver for Marvell Armada 370/XP network unit This patch contains a new network driver for the network unit of the ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B processor, a Marvell-developed ARM core that implements the ARMv7 instruction set. Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery), the network unit in Armada 370 and Armada XP is highly different. This is the reason why this new 'mvneta' driver is needed, while the older ARM Marvell SoCs use the 'mv643xx_eth' driver. Here is an overview of the most important hardware changes that require a new, specific, driver for the network unit of Armada 370/XP: - The new network unit has a completely different design and layout for the RX and TX descriptors. They are now organized as a simple array (each RX and TX queue has base address and size of this array) rather than a linked list as in the old SoCs. - The new network unit has a different RXQ and TXQ management: this management is done using special read/write counter registers, while in the Old SocS, it was done using the Ownership bit in RX and TX descriptors. - The new network unit has different interrupt registers - The new network unit way of cleaning of interrupts is not done by writing to the cause register, but by updating per-queue counters - The new network unit has different GMAC registers (link, speed, duplex configuration) and different WRR registers. - The new network unit has lots of new units like PnC (Parser and Classifier), PMT, BM (Memory Buffer Management), xPON, and more. The driver proposed in the current patch only handles the basic features. Additional hardware features will progressively be supported as needed. This code has originally been written by Rami Rosen <rosenr@marvell.com>, and then reviewed and cleaned up by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-17 19:04:28 +08:00
Example:
net: mvneta: bm: add support for hardware buffer management Buffer manager (BM) is a dedicated hardware unit that can be used by all ethernet ports of Armada XP and 38x SoC's. It allows to offload CPU on RX path by sparing DRAM access on refilling buffer pool, hardware-based filling of descriptor ring data and better memory utilization due to HW arbitration for using 'short' pools for small packets. Tests performed with A388 SoC working as a network bridge between two packet generators showed increase of maximum processed 64B packets by ~20k (~555k packets with BM enabled vs ~535 packets without BM). Also when pushing 1500B-packets with a line rate achieved, CPU load decreased from around 25% without BM to 20% with BM. BM comprise up to 4 buffer pointers' (BP) rings kept in DRAM, which are called external BP pools - BPPE. Allocating and releasing buffer pointers (BP) to/from BPPE is performed indirectly by write/read access to a dedicated internal SRAM, where internal BP pools (BPPI) are placed. BM hardware controls status of BPPE automatically, as well as assigning proper buffers to RX descriptors. For more details please refer to Functional Specification of Armada XP or 38x SoC. In order to enable support for a separate hardware block, common for all ports, a new driver has to be implemented ('mvneta_bm'). It provides initialization sequence of address space, clocks, registers, SRAM, empty pools' structures and also obtaining optional configuration from DT (please refer to device tree binding documentation). mvneta_bm exposes also a necessary API to mvneta driver, as well as a dedicated structure with BM information (bm_priv), whose presence is used as a flag notifying of BM usage by port. It has to be ensured that mvneta_bm probe is executed prior to the ones in ports' driver. In case BM is not used or its probe fails, mvneta falls back to use software buffer management. A sequence executed in mvneta_probe function is modified in order to have an access to needed resources before possible port's BM initialization is done. According to port-pools mapping provided by DT appropriate registers are configured and the buffer pools are filled. RX path is modified accordingly. Becaues the hardware allows a wide variety of configuration options, following assumptions are made: * using BM mechanisms can be selectively disabled/enabled basing on DT configuration among the ports * 'long' pool's single buffer size is tied to port's MTU * using 'long' pool by port is obligatory and it cannot be shared * using 'short' pool for smaller packets is optional * one 'short' pool can be shared among all ports This commit enables hardware buffer management operation cooperating with existing mvneta driver. New device tree binding documentation is added and the one of mvneta is updated accordingly. [gregory.clement@free-electrons.com: removed the suspend/resume part] Signed-off-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 16:39:03 +08:00
ethernet@70000 {
net: mvneta: driver for Marvell Armada 370/XP network unit This patch contains a new network driver for the network unit of the ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B processor, a Marvell-developed ARM core that implements the ARMv7 instruction set. Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery), the network unit in Armada 370 and Armada XP is highly different. This is the reason why this new 'mvneta' driver is needed, while the older ARM Marvell SoCs use the 'mv643xx_eth' driver. Here is an overview of the most important hardware changes that require a new, specific, driver for the network unit of Armada 370/XP: - The new network unit has a completely different design and layout for the RX and TX descriptors. They are now organized as a simple array (each RX and TX queue has base address and size of this array) rather than a linked list as in the old SoCs. - The new network unit has a different RXQ and TXQ management: this management is done using special read/write counter registers, while in the Old SocS, it was done using the Ownership bit in RX and TX descriptors. - The new network unit has different interrupt registers - The new network unit way of cleaning of interrupts is not done by writing to the cause register, but by updating per-queue counters - The new network unit has different GMAC registers (link, speed, duplex configuration) and different WRR registers. - The new network unit has lots of new units like PnC (Parser and Classifier), PMT, BM (Memory Buffer Management), xPON, and more. The driver proposed in the current patch only handles the basic features. Additional hardware features will progressively be supported as needed. This code has originally been written by Rami Rosen <rosenr@marvell.com>, and then reviewed and cleaned up by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-17 19:04:28 +08:00
compatible = "marvell,armada-370-neta";
net: mvneta: bm: add support for hardware buffer management Buffer manager (BM) is a dedicated hardware unit that can be used by all ethernet ports of Armada XP and 38x SoC's. It allows to offload CPU on RX path by sparing DRAM access on refilling buffer pool, hardware-based filling of descriptor ring data and better memory utilization due to HW arbitration for using 'short' pools for small packets. Tests performed with A388 SoC working as a network bridge between two packet generators showed increase of maximum processed 64B packets by ~20k (~555k packets with BM enabled vs ~535 packets without BM). Also when pushing 1500B-packets with a line rate achieved, CPU load decreased from around 25% without BM to 20% with BM. BM comprise up to 4 buffer pointers' (BP) rings kept in DRAM, which are called external BP pools - BPPE. Allocating and releasing buffer pointers (BP) to/from BPPE is performed indirectly by write/read access to a dedicated internal SRAM, where internal BP pools (BPPI) are placed. BM hardware controls status of BPPE automatically, as well as assigning proper buffers to RX descriptors. For more details please refer to Functional Specification of Armada XP or 38x SoC. In order to enable support for a separate hardware block, common for all ports, a new driver has to be implemented ('mvneta_bm'). It provides initialization sequence of address space, clocks, registers, SRAM, empty pools' structures and also obtaining optional configuration from DT (please refer to device tree binding documentation). mvneta_bm exposes also a necessary API to mvneta driver, as well as a dedicated structure with BM information (bm_priv), whose presence is used as a flag notifying of BM usage by port. It has to be ensured that mvneta_bm probe is executed prior to the ones in ports' driver. In case BM is not used or its probe fails, mvneta falls back to use software buffer management. A sequence executed in mvneta_probe function is modified in order to have an access to needed resources before possible port's BM initialization is done. According to port-pools mapping provided by DT appropriate registers are configured and the buffer pools are filled. RX path is modified accordingly. Becaues the hardware allows a wide variety of configuration options, following assumptions are made: * using BM mechanisms can be selectively disabled/enabled basing on DT configuration among the ports * 'long' pool's single buffer size is tied to port's MTU * using 'long' pool by port is obligatory and it cannot be shared * using 'short' pool for smaller packets is optional * one 'short' pool can be shared among all ports This commit enables hardware buffer management operation cooperating with existing mvneta driver. New device tree binding documentation is added and the one of mvneta is updated accordingly. [gregory.clement@free-electrons.com: removed the suspend/resume part] Signed-off-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 16:39:03 +08:00
reg = <0x70000 0x2500>;
net: mvneta: driver for Marvell Armada 370/XP network unit This patch contains a new network driver for the network unit of the ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B processor, a Marvell-developed ARM core that implements the ARMv7 instruction set. Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery), the network unit in Armada 370 and Armada XP is highly different. This is the reason why this new 'mvneta' driver is needed, while the older ARM Marvell SoCs use the 'mv643xx_eth' driver. Here is an overview of the most important hardware changes that require a new, specific, driver for the network unit of Armada 370/XP: - The new network unit has a completely different design and layout for the RX and TX descriptors. They are now organized as a simple array (each RX and TX queue has base address and size of this array) rather than a linked list as in the old SoCs. - The new network unit has a different RXQ and TXQ management: this management is done using special read/write counter registers, while in the Old SocS, it was done using the Ownership bit in RX and TX descriptors. - The new network unit has different interrupt registers - The new network unit way of cleaning of interrupts is not done by writing to the cause register, but by updating per-queue counters - The new network unit has different GMAC registers (link, speed, duplex configuration) and different WRR registers. - The new network unit has lots of new units like PnC (Parser and Classifier), PMT, BM (Memory Buffer Management), xPON, and more. The driver proposed in the current patch only handles the basic features. Additional hardware features will progressively be supported as needed. This code has originally been written by Rami Rosen <rosenr@marvell.com>, and then reviewed and cleaned up by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-17 19:04:28 +08:00
interrupts = <8>;
clocks = <&gate_clk 4>;
tx-csum-limit = <9800>
net: mvneta: driver for Marvell Armada 370/XP network unit This patch contains a new network driver for the network unit of the ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B processor, a Marvell-developed ARM core that implements the ARMv7 instruction set. Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery), the network unit in Armada 370 and Armada XP is highly different. This is the reason why this new 'mvneta' driver is needed, while the older ARM Marvell SoCs use the 'mv643xx_eth' driver. Here is an overview of the most important hardware changes that require a new, specific, driver for the network unit of Armada 370/XP: - The new network unit has a completely different design and layout for the RX and TX descriptors. They are now organized as a simple array (each RX and TX queue has base address and size of this array) rather than a linked list as in the old SoCs. - The new network unit has a different RXQ and TXQ management: this management is done using special read/write counter registers, while in the Old SocS, it was done using the Ownership bit in RX and TX descriptors. - The new network unit has different interrupt registers - The new network unit way of cleaning of interrupts is not done by writing to the cause register, but by updating per-queue counters - The new network unit has different GMAC registers (link, speed, duplex configuration) and different WRR registers. - The new network unit has lots of new units like PnC (Parser and Classifier), PMT, BM (Memory Buffer Management), xPON, and more. The driver proposed in the current patch only handles the basic features. Additional hardware features will progressively be supported as needed. This code has originally been written by Rami Rosen <rosenr@marvell.com>, and then reviewed and cleaned up by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-17 19:04:28 +08:00
phy = <&phy0>;
phy-mode = "rgmii-id";
net: mvneta: bm: add support for hardware buffer management Buffer manager (BM) is a dedicated hardware unit that can be used by all ethernet ports of Armada XP and 38x SoC's. It allows to offload CPU on RX path by sparing DRAM access on refilling buffer pool, hardware-based filling of descriptor ring data and better memory utilization due to HW arbitration for using 'short' pools for small packets. Tests performed with A388 SoC working as a network bridge between two packet generators showed increase of maximum processed 64B packets by ~20k (~555k packets with BM enabled vs ~535 packets without BM). Also when pushing 1500B-packets with a line rate achieved, CPU load decreased from around 25% without BM to 20% with BM. BM comprise up to 4 buffer pointers' (BP) rings kept in DRAM, which are called external BP pools - BPPE. Allocating and releasing buffer pointers (BP) to/from BPPE is performed indirectly by write/read access to a dedicated internal SRAM, where internal BP pools (BPPI) are placed. BM hardware controls status of BPPE automatically, as well as assigning proper buffers to RX descriptors. For more details please refer to Functional Specification of Armada XP or 38x SoC. In order to enable support for a separate hardware block, common for all ports, a new driver has to be implemented ('mvneta_bm'). It provides initialization sequence of address space, clocks, registers, SRAM, empty pools' structures and also obtaining optional configuration from DT (please refer to device tree binding documentation). mvneta_bm exposes also a necessary API to mvneta driver, as well as a dedicated structure with BM information (bm_priv), whose presence is used as a flag notifying of BM usage by port. It has to be ensured that mvneta_bm probe is executed prior to the ones in ports' driver. In case BM is not used or its probe fails, mvneta falls back to use software buffer management. A sequence executed in mvneta_probe function is modified in order to have an access to needed resources before possible port's BM initialization is done. According to port-pools mapping provided by DT appropriate registers are configured and the buffer pools are filled. RX path is modified accordingly. Becaues the hardware allows a wide variety of configuration options, following assumptions are made: * using BM mechanisms can be selectively disabled/enabled basing on DT configuration among the ports * 'long' pool's single buffer size is tied to port's MTU * using 'long' pool by port is obligatory and it cannot be shared * using 'short' pool for smaller packets is optional * one 'short' pool can be shared among all ports This commit enables hardware buffer management operation cooperating with existing mvneta driver. New device tree binding documentation is added and the one of mvneta is updated accordingly. [gregory.clement@free-electrons.com: removed the suspend/resume part] Signed-off-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-14 16:39:03 +08:00
buffer-manager = <&bm>;
bm,pool-long = <0>;
bm,pool-short = <1>;
net: mvneta: driver for Marvell Armada 370/XP network unit This patch contains a new network driver for the network unit of the ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B processor, a Marvell-developed ARM core that implements the ARMv7 instruction set. Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery), the network unit in Armada 370 and Armada XP is highly different. This is the reason why this new 'mvneta' driver is needed, while the older ARM Marvell SoCs use the 'mv643xx_eth' driver. Here is an overview of the most important hardware changes that require a new, specific, driver for the network unit of Armada 370/XP: - The new network unit has a completely different design and layout for the RX and TX descriptors. They are now organized as a simple array (each RX and TX queue has base address and size of this array) rather than a linked list as in the old SoCs. - The new network unit has a different RXQ and TXQ management: this management is done using special read/write counter registers, while in the Old SocS, it was done using the Ownership bit in RX and TX descriptors. - The new network unit has different interrupt registers - The new network unit way of cleaning of interrupts is not done by writing to the cause register, but by updating per-queue counters - The new network unit has different GMAC registers (link, speed, duplex configuration) and different WRR registers. - The new network unit has lots of new units like PnC (Parser and Classifier), PMT, BM (Memory Buffer Management), xPON, and more. The driver proposed in the current patch only handles the basic features. Additional hardware features will progressively be supported as needed. This code has originally been written by Rami Rosen <rosenr@marvell.com>, and then reviewed and cleaned up by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Acked-by: David S. Miller <davem@davemloft.net>
2012-08-17 19:04:28 +08:00
};