Hi Andy, On Fri, Sep 04, 2020 at 10:12:07PM +0300, Andy Shevchenko wrote: > On Fri, Sep 4, 2020 at 7:52 PM Vadym Kochan <vadym.koc...@plvision.eu> wrote: > > > > Marvell Prestera 98DX326x integrates up to 24 ports of 1GbE with 8 > > ports of 10GbE uplinks or 2 ports of 40Gbps stacking for a largely > > wireless SMB deployment. > > > > The current implementation supports only boards designed for the Marvell > > Switchdev solution and requires special firmware. > > > > The core Prestera switching logic is implemented in prestera_main.c, > > there is an intermediate hw layer between core logic and firmware. It is > > implemented in prestera_hw.c, the purpose of it is to encapsulate hw > > related logic, in future there is a plan to support more devices with > > different HW related configurations. > > > > This patch contains only basic switch initialization and RX/TX support > > over SDMA mechanism. > > > > Currently supported devices have DMA access range <= 32bit and require > > ZONE_DMA to be enabled, for such cases SDMA driver checks if the skb > > allocated in proper range supported by the Prestera device. > > > > Also meanwhile there is no TX interrupt support in current firmware > > version so recycling work is scheduled on each xmit. > > > > Port's mac address is generated from the switch base mac which may be > > provided via device-tree (static one or as nvme cell), or randomly > > generated. This is required by the firmware. > > ... > > > +#define prestera_dev(sw) ((sw)->dev->dev) > > The point of this is...? (What I see it's 2 characters longer) > > ... It is not about the length but rather about easier semantics, so the prestera_dev() is more easier to remember than sw->dev->dev.
> > > + words[0] = ntohl(dsa_words[0]); > > + words[1] = ntohl(dsa_words[1]); > > + words[2] = ntohl(dsa_words[2]); > > + words[3] = ntohl(dsa_words[3]); > > This is (semi-)NIH of be32_to_cpu_array() > > You may add an additional patch to provide ntohl_array() as an alias > how it's done for the rest: > https://elixir.bootlin.com/linux/v5.9-rc3/source/include/linux/byteorder/generic.h#L123 > > ... > > > + dsa->vlan.vid &= ~PRESTERA_VID_MASK; > > + dsa->vlan.vid |= FIELD_PREP(PRESTERA_VID_MASK, field); > > Consider to use uXX_replace_bits() (XX for size of the variable). > Look at bitfield.h closer. > > ... > > > + dsa->hw_dev_num &= PRESTERA_W3_HW_DEV_NUM; > > + dsa->hw_dev_num |= FIELD_PREP(PRESTERA_DEV_NUM_MASK, field); > > Ditto? (Not sure why first line w/o _MASK) > > ... > > > + if (dsa->hw_dev_num >= BIT(12)) > > + return -EINVAL; > > + if (dsa->port_num >= BIT(17)) > > + return -EINVAL; > > Magic numbers! > > ... > > > + words[3] |= FIELD_PREP(PRESTERA_W3_HW_DEV_NUM, (dsa->hw_dev_num >> > > 5)); > > Ditto. > > ... > > > + dsa_words[0] = htonl(words[0]); > > + dsa_words[1] = htonl(words[1]); > > + dsa_words[2] = htonl(words[2]); > > + dsa_words[3] = htonl(words[3]); > > NIH of cpu_to_be32_array(). > > ... > > > +/* > > + * Copyright (c) 2020 Marvell International Ltd. All rights reserved. > > + * > > + */ > > One line. > > ... > > > + err = prestera_find_event_handler(sw, msg->type, &eh); > > > + if (err || !fw_event_parsers[msg->type].func) > > + return -EEXIST; > > Why shadowing error code? > > ... > > > + struct prestera_msg_port_info_req req = { > > + .port = port->id > > Leave comma here. > Another possibility, if you not expect this to grow, move to one line. > > > + }; > > ... > > > + .param = {.admin_state = admin_state} > > + white spaces? Whatever you choose, just be consistent among all > similar definitions. > > ... > > > + .port = port->hw_id, > > + .dev = port->dev_id > > Leave comma. > > ... > > > + struct prestera_msg_port_attr_req req = { > > + .attr = PRESTERA_CMD_PORT_ATTR_CAPABILITY, > > + .port = port->hw_id, > > + .dev = port->dev_id > > Ditto. I have a deja vu that I already pointed out to these. > > > + }; > > ... > > > + err = prestera_cmd_ret(port->sw, PRESTERA_CMD_TYPE_PORT_ATTR_GET, > > + &req.cmd, sizeof(req), &resp.ret, > > sizeof(resp)); > > + if (err) > > + return err; > > + > > + caps->supp_link_modes = resp.param.cap.link_mode; > > + caps->supp_fec = resp.param.cap.fec; > > + caps->type = resp.param.cap.type; > > + caps->transceiver = resp.param.cap.transceiver; > > + > > > + return err; > > return 0; > > > +} > > ... > > > + .param = {.autoneg = {.link_mode = link_modes, > > + .enable = autoneg, > > + .fec = fec} > > Fix indentation and style. > > > + } > > ... > > > + struct prestera_msg_port_attr_req req = { > > + .attr = PRESTERA_CMD_PORT_ATTR_STATS, > > + .port = port->hw_id, > > + .dev = port->dev_id > > + Comma. > > > + }; > > ... > > > +/* > > + * Copyright (c) 2019-2020 Marvell International Ltd. All rights reserved. > > + * > > + */ > > One line. > > ... > > > +#include <linux/kernel.h> > > +#include <linux/module.h> > > +#include <linux/list.h> > > +#include <linux/netdevice.h> > > +#include <linux/netdev_features.h> > > +#include <linux/etherdevice.h> > > +#include <linux/jiffies.h> > > +#include <linux/of.h> > > +#include <linux/of_net.h> > > Perhaps sorted? > > ... > > > +static int prestera_port_state_set(struct net_device *dev, bool is_up) > > +{ > > + struct prestera_port *port = netdev_priv(dev); > > + int err; > > + > > + if (is_up) { > > + err = prestera_hw_port_state_set(port, true); > > + if (err) > > + return err; > > + > > + netif_start_queue(dev); > > + } else { > > + netif_stop_queue(dev); > > + > > + err = prestera_hw_port_state_set(port, false); > > + if (err) > > + return err; > > + } > > + > > + return 0; > > +} > > + > > +static int prestera_port_open(struct net_device *dev) > > +{ > > + return prestera_port_state_set(dev, true); > > +} > > + > > +static int prestera_port_close(struct net_device *dev) > > +{ > > + return prestera_port_state_set(dev, false); > > +} > > What the point to have above function if you simple can put its > contents in these two? > This is really makes sense. > ... > > > + /* firmware requires that port's mac address contains first 5 bytes > > + * of base mac address > > mac -> MAC? (two cases) > > > + */ > > ... > > > +static int prestera_port_autoneg_set(struct prestera_port *port, bool > > enable, > > + u64 link_modes, u8 fec) > > +{ > > + bool refresh = false; > > > + int err = 0; > > Redundant assignment. > > > + if (port->caps.type != PRESTERA_PORT_TYPE_TP) > > + return enable ? -EINVAL : 0; > > + > > + if (port->adver_link_modes != link_modes || port->adver_fec != fec) > > { > > + port->adver_fec = fec ?: BIT(PRESTERA_PORT_FEC_OFF); > > + port->adver_link_modes = link_modes; > > + refresh = true; > > + } > > + > > + if (port->autoneg == enable && !(port->autoneg && refresh)) > > + return 0; > > + > > + err = prestera_hw_port_autoneg_set(port, enable, > > port->adver_link_modes, > > + port->adver_fec); > > + if (err) > > > + return -EINVAL; > > Why shadowed? > > > + port->autoneg = enable; > > + return 0; > > +} > > ... > > > + /* firmware requires that port's mac address consist of the first > > + * 5 bytes of base mac address > > + */ > > > > + memcpy(dev->dev_addr, sw->base_mac, dev->addr_len - 1); > > Can't you call above helper for that? Not sure if I got this right, but I assume that may be just use ether_addr_copy() and then just perform the below assignment on the last byte ? > > ... > > > + dev->dev_addr[dev->addr_len - 1] = (char)port->fp_id; > > Why explicit casting? > > ... > > > +static int prestera_switch_set_base_mac_addr(struct prestera_switch *sw) > > +{ > > + struct device_node *base_mac_np; > > + struct device_node *np; > > + > > + np = of_find_compatible_node(NULL, NULL, "marvell,prestera"); > > > + if (np) { > > I think it's useless check, b/c... > > > + base_mac_np = of_parse_phandle(np, "base-mac-provider", 0); > > ...this will return error. > > So, something like struct device_node *np = of_find_...(...); above. > > > + if (base_mac_np) { > > I think it's useless check. > Similar as above. > Really! > > + const char *base_mac; > > + > > + base_mac = of_get_mac_address(base_mac_np); > > + of_node_put(base_mac_np); > > + if (!IS_ERR(base_mac)) > > + ether_addr_copy(sw->base_mac, base_mac); > > + } > > + } > > + if (!is_valid_ether_addr(sw->base_mac)) { > > + eth_random_addr(sw->base_mac); > > + dev_info(sw->dev->dev, "using random base mac address\n"); > > + } > > + > > + return prestera_hw_switch_mac_set(sw, sw->base_mac); > > +} > > ... > > > +int prestera_device_register(struct prestera_device *dev) > > +{ > > + struct prestera_switch *sw; > > + int err; > > + > > + sw = kzalloc(sizeof(*sw), GFP_KERNEL); > > + if (!sw) > > + return -ENOMEM; > > + > > + dev->priv = sw; > > + sw->dev = dev; > > + > > + err = prestera_switch_init(sw); > > + if (err) { > > + kfree(sw); > > > + return err; > > + } > > + > > + return 0; > > return err; > > > +} > > ... > > > +#include <linux/dmapool.h> > > +#include <linux/etherdevice.h> > > +#include <linux/if_vlan.h> > > +#include <linux/of.h> > > +#include <linux/of_address.h> > > +#include <linux/of_device.h> > > +#include <linux/netdevice.h> > > +#include <linux/platform_device.h> > > ... > > > +#define PRESTERA_SDMA_RX_DESC_IS_RCVD(desc) \ > > + (PRESTERA_SDMA_RX_DESC_OWNER((desc)) == > > PRESTERA_SDMA_RX_DESC_CPU_OWN) > > Double (()) make no sense here. > > ... > > > +static void prestera_sdma_rx_desc_set_len(struct prestera_sdma_desc *desc, > > + size_t val) > > +{ > > + u32 word = le32_to_cpu(desc->word2); > > + > > + word = (word & ~GENMASK(15, 0)) | val; > > + desc->word2 = cpu_to_le32(word); > > +} > > Why not simple le32_replace_bits() ? > I was not aware of these helpers, thanks. > ... > > > + port = prestera_port_find_by_hwid(sdma->sw, dev_id, hw_port); > > + if (unlikely(!port)) { > > > + pr_warn_ratelimited("received pkt for non-existent port(%u, > > %u)\n", > > + dev_id, hw_port); > > What's wrong with dev_warn_ratelimited() ? > I will use it, thanks. > > + return -EEXIST; > > + } > > ... > > > + for (b = 0; b < bnum; b++) { > > + struct prestera_sdma_buf *buf = &ring->bufs[b]; > > + > > + err = prestera_sdma_buf_init(sdma, buf); > > + if (err) > > + return err; > > + > > + err = prestera_sdma_rx_skb_alloc(sdma, buf); > > + if (err) > > No need to uninit previously init buffers? > No need to dealloc previously allocated stuff? > > > + return err; This is done in the prestera_rxtx.c:prestera_sdma_switch_init() caller which calls the generic rx_uninit() on error path handling. > > ... > > > + if (b == 0) > > + continue; > > + > > + prestera_sdma_rx_desc_set_next(sdma, > > + ring->bufs[b - > > 1].desc, > > + buf->desc_dma); > > + > > + if (b == PRESTERA_SDMA_RX_DESC_PER_Q - 1) > > + prestera_sdma_rx_desc_set_next(sdma, > > buf->desc, > > + > > head->desc_dma); > > I guess knowing what the allowed range of bnum the above can be optimized. > > > + } I will think of this, thanks. > > ... > > > + u32 word = le32_to_cpu(desc->word2); > > + > > + word = (word & ~GENMASK(30, 16)) | ((len + ETH_FCS_LEN) << 16); > > + > > + desc->word2 = cpu_to_le32(word); > > le32_replace_bits() > > ... > > > +static void prestera_sdma_tx_desc_xmit(struct prestera_sdma_desc *desc) > > +{ > > + u32 word = le32_to_cpu(desc->word1); > > + > > + word |= PRESTERA_SDMA_TX_DESC_DMA_OWN << 31; > > + > > + /* make sure everything is written before enable xmit */ > > + wmb(); > > + > > + desc->word1 = cpu_to_le32(word); > > Seems to me it's also safe to use le32_replace_bits(), but I'm not > sure if desc->word1 can be changed after barrier by somebody else. > > > +} > > ... > > > + for (b = 0; b < bnum; b++) { > > + struct prestera_sdma_buf *buf = &tx_ring->bufs[b]; > > + > > + err = prestera_sdma_buf_init(sdma, buf); > > + if (err) > > + return err; > > + > > + prestera_sdma_tx_desc_init(sdma, buf->desc); > > + > > + buf->is_used = false; > > + > > + if (b == 0) > > + continue; > > + > > + prestera_sdma_tx_desc_set_next(sdma, tx_ring->bufs[b - > > 1].desc, > > + buf->desc_dma); > > + > > + if (b == PRESTERA_SDMA_TX_DESC_PER_Q - 1) > > + prestera_sdma_tx_desc_set_next(sdma, buf->desc, > > + head->desc_dma); > > + } > > Similar comments as per above similar for-loop. > > ... > > > +static int prestera_sdma_tx_wait(struct prestera_sdma *sdma, > > + struct prestera_tx_ring *tx_ring) > > +{ > > + int tx_retry_num = PRESTERA_SDMA_WAIT_MUL * tx_ring->max_burst; > > + > > + do { > > + if (prestera_sdma_is_ready(sdma)) > > + return 0; > > + > > + udelay(1); > > + } while (--tx_retry_num); > > + > > + return -EBUSY; > > +} > > iopoll.h > readx_poll_timeout(). > > ... > > > +/* > > + * Copyright (c) 2019-2020 Marvell International Ltd. All rights reserved. > > + * > > + */ > > One line. > > ... > > > +#include "prestera.h" > > I don't see users of the above header here. You may use declarations instead. > > > +int prestera_rxtx_switch_init(struct prestera_switch *sw); > > +void prestera_rxtx_switch_fini(struct prestera_switch *sw); > > + > > +int prestera_rxtx_port_init(struct prestera_port *port); > > + > > +netdev_tx_t prestera_rxtx_xmit(struct prestera_port *port, struct sk_buff > > *skb); > > -- > With Best Regards, > Andy Shevchenko Thanks a lot!
