RE: [PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up

Frank Li
2022-10-06T14:26:38Z

> -----Original Message-----
> From: Frank Li
> Sent: Thursday, September 22, 2022 11:14 AM
> To: maz@kernel.org; tglx@linutronix.de; robh+dt@kernel.org;
> krzysztof.kozlowski+dt@linaro.org; shawnguo@kernel.org;
> s.hauer@pengutronix.de; kw@linux.com; bhelgaas@google.com
> Cc: linux-kernel@vger.kernel.org; devicetree@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org; linux-pci@vger.kernel.org; Peng Fan
> <peng.fan@nxp.com>; Aisheng Dong <aisheng.dong@nxp.com>;
> jdmason@kudzu.us; kernel@pengutronix.de; festevam@gmail.com; dl-linux-
> imx <linux-imx@nxp.com>; kishon@ti.com; lorenzo.pieralisi@arm.com;
> ntb@lists.linux.dev; lznuaa@gmail.com; imx@lists.linux.dev;
> manivannan.sadhasivam@linaro.org
> Subject: [PATCH v12 5/6] PCI: endpoint: pci-epf-vntb: Clean up
>

[Frank Li] @Bjorn Helgaas, ping
Patches[1-4] was already picked by irqchip.
I think patch[5-6] should go through pci subsystem.
Any additional comments?

> Remove unused field: epf_db_phy.
> Remove __iomem before epf_db.
> Change epf_db to u32* from void *
> Remove duplicate check if (readl(ntb->epf_db + i * 4)).
> Using sizeof(u32) instead of number 4 at all place.
>
> Clean up sparse build warning:
> Using epf_db[i] instead of readl() because epf_db is located in local
> memory and allocated by dma_alloc_coherent(). Sparse build warning
> when
> there are not __iomem at readl().
> Added __iomem force type convert in vntb_epf_peer_spad_read\write()
> and
> vntb_epf_spad_read\write(). This require strong order at read and write.
>
> Replace pci_epc_mem_free_addr() with pci_epf_free_space() at error handle
> path to match pci_epf_alloc_space().
>
> Cleanup warning found by scripts/kernel-doc
> Fix indentation of the struct epf_ntb_ctrl
> Consolidate term
> host, host1 to HOST
> vhost, vHost, Vhost, VHOST2 to VHOST
>
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> drivers/pci/endpoint/functions/pci-epf-vntb.c | 157 ++++++++++--------
> 1 file changed, 90 insertions(+), 67 deletions(-)
>
> diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> index 1466dd1904175..acea753af29ed 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> @@ -11,7 +11,7 @@
> * Author: Kishon Vijay Abraham I <kishon@ti.com>
> */
>
> -/**
> +/*
> * +------------+ +---------------------------------------+
> * | | | |
> * +------------+ | +--------------+
> @@ -99,20 +99,20 @@ enum epf_ntb_bar {
> * NTB Driver NTB Driver
> */
> struct epf_ntb_ctrl {
> - u32 command;
> - u32 argument;
> - u16 command_status;
> - u16 link_status;
> - u32 topology;
> - u64 addr;
> - u64 size;
> - u32 num_mws;
> - u32 reserved;
> - u32 spad_offset;
> - u32 spad_count;
> - u32 db_entry_size;
> - u32 db_data[MAX_DB_COUNT];
> - u32 db_offset[MAX_DB_COUNT];
> + u32 command;
> + u32 argument;
> + u16 command_status;
> + u16 link_status;
> + u32 topology;
> + u64 addr;
> + u64 size;
> + u32 num_mws;
> + u32 reserved;
> + u32 spad_offset;
> + u32 spad_count;
> + u32 db_entry_size;
> + u32 db_data[MAX_DB_COUNT];
> + u32 db_offset[MAX_DB_COUNT];
> } __packed;
>
> struct epf_ntb {
> @@ -136,8 +136,7 @@ struct epf_ntb {
>
> struct epf_ntb_ctrl *reg;
>
> - phys_addr_t epf_db_phy;
> - void __iomem *epf_db;
> + u32 *epf_db;
>
> phys_addr_t vpci_mw_phy[MAX_MW];
> void __iomem *vpci_mw_addr[MAX_MW];
> @@ -156,12 +155,14 @@ static struct pci_epf_header epf_ntb_header = {
> };
>
> /**
> - * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host
> + * epf_ntb_link_up() - Raise link_up interrupt to Virtual Host (VHOST)
> * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> * @link_up: true or false indicating Link is UP or Down
> *
> * Once NTB function in HOST invoke ntb_link_enable(),
> - * this NTB function driver will trigger a link event to vhost.
> + * this NTB function driver will trigger a link event to VHOST.
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
> {
> @@ -175,9 +176,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> link_up)
> }
>
> /**
> - * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> vhost
> - * to access the memory window of host
> - * @ntb: NTB device that facilitates communication between host and vhost
> + * epf_ntb_configure_mw() - Configure the Outbound Address Space for
> VHOST
> + * to access the memory window of HOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> * @mw: Index of the memory window (either 0, 1, 2 or 3)
> *
> * EP Outbound Window
> @@ -194,7 +195,9 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool
> link_up)
> * | | | |
> * | | | |
> * +--------+ +-----------+
> - * VHost PCI EP
> + * VHOST PCI EP
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_configure_mw(struct epf_ntb *ntb, u32 mw)
> {
> @@ -219,7 +222,7 @@ static int epf_ntb_configure_mw(struct epf_ntb *ntb,
> u32 mw)
>
> /**
> * epf_ntb_teardown_mw() - Teardown the configured OB ATU
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> * @mw: Index of the memory window (either 0, 1, 2 or 3)
> *
> * Teardown the configured OB ATU configured in epf_ntb_configure_mw()
> using
> @@ -234,12 +237,12 @@ static void epf_ntb_teardown_mw(struct epf_ntb
> *ntb, u32 mw)
> }
>
> /**
> - * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
> + * epf_ntb_cmd_handler() - Handle commands provided by the NTB HOST
> * @work: work_struct for the epf_ntb_epc
> *
> * Workqueue function that gets invoked for the two epf_ntb_epc
> * periodically (once every 5ms) to see if it has received any commands
> - * from NTB host. The host can send commands to configure doorbell or
> + * from NTB HOST. The HOST can send commands to configure doorbell or
> * configure memory window or to update link status.
> */
> static void epf_ntb_cmd_handler(struct work_struct *work)
> @@ -254,12 +257,9 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
> ntb = container_of(work, struct epf_ntb, cmd_handler.work);
>
> for (i = 1; i < ntb->db_count; i++) {
> - if (readl(ntb->epf_db + i * 4)) {
> - if (readl(ntb->epf_db + i * 4))
> - ntb->db |= 1 << (i - 1);
> -
> + if (ntb->epf_db[i]) {
> ntb_db_event(&ntb->ntb, i);
> - writel(0, ntb->epf_db + i * 4);
> + ntb->epf_db[i] = 0;
> }
> }
>
> @@ -321,8 +321,8 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
>
> /**
> * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
> - * @ntb_epc: EPC associated with one of the HOST which holds peer's
> outbound
> - * address.
> + * @ntb: EPC associated with one of the HOST which holds peer's outbound
> + * address.
> *
> * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
> * self scratchpad region (removes inbound ATU configuration). While BAR0
> is
> @@ -331,8 +331,10 @@ static void epf_ntb_cmd_handler(struct work_struct
> *work)
> * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
> *
> * Please note the self scratchpad region and config region is combined to
> - * a single region and mapped using the same BAR. Also note HOST2's peer
> - * scratchpad is HOST1's self scratchpad.
> + * a single region and mapped using the same BAR. Also note VHOST's peer
> + * scratchpad is HOST's self scratchpad.
> + *
> + * Returns: void
> */
> static void epf_ntb_config_sspad_bar_clear(struct epf_ntb *ntb)
> {
> @@ -347,13 +349,15 @@ static void epf_ntb_config_sspad_bar_clear(struct
> epf_ntb *ntb)
>
> /**
> * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> *
> - * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
> + * Map BAR0 of EP CONTROLLER which contains the VHOST's config and
> * self scratchpad region.
> *
> * Please note the self scratchpad region and config region is combined to
> * a single region and mapped using the same BAR.
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_config_sspad_bar_set(struct epf_ntb *ntb)
> {
> @@ -380,7 +384,7 @@ static int epf_ntb_config_sspad_bar_set(struct
> epf_ntb *ntb)
> /**
> * epf_ntb_config_spad_bar_free() - Free the physical memory associated
> with
> * config + scratchpad region
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> */
> static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
> {
> @@ -393,11 +397,13 @@ static void epf_ntb_config_spad_bar_free(struct
> epf_ntb *ntb)
> /**
> * epf_ntb_config_spad_bar_alloc() - Allocate memory for config +
> scratchpad
> * region
> - * @ntb: NTB device that facilitates communication between HOST1 and
> HOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> *
> * Allocate the Local Memory mentioned in the above diagram. The size of
> * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD
> REGION
> * is obtained from "spad-count" configfs entry.
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
> {
> @@ -424,7 +430,7 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
> spad_count = ntb->spad_count;
>
> ctrl_size = sizeof(struct epf_ntb_ctrl);
> - spad_size = 2 * spad_count * 4;
> + spad_size = 2 * spad_count * sizeof(u32);
>
> if (!align) {
> ctrl_size = roundup_pow_of_two(ctrl_size);
> @@ -454,7 +460,7 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
> ctrl->num_mws = ntb->num_mws;
> ntb->spad_size = spad_size;
>
> - ctrl->db_entry_size = 4;
> + ctrl->db_entry_size = sizeof(u32);
>
> for (i = 0; i < ntb->db_count; i++) {
> ntb->reg->db_data[i] = 1 + i;
> @@ -465,11 +471,13 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb)
> }
>
> /**
> - * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capaiblity
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> *
> * Configure MSI/MSI-X capability for each interface with number of
> * interrupts equal to "db_count" configfs entry.
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
> {
> @@ -511,18 +519,22 @@ static int epf_ntb_configure_interrupt(struct
> epf_ntb *ntb)
>
> /**
> * epf_ntb_db_bar_init() - Configure Doorbell window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
> {
> const struct pci_epc_features *epc_features;
> - u32 align;
> struct device *dev = &ntb->epf->dev;
> - int ret;
> struct pci_epf_bar *epf_bar;
> - void __iomem *mw_addr;
> enum pci_barno barno;
> - size_t size = 4 * ntb->db_count;
> + void *mw_addr;
> + size_t size;
> + u32 align;
> + int ret;
> +
> + size = sizeof(u32) * ntb->db_count;
>
> epc_features = pci_epc_get_features(ntb->epf->epc,
> ntb->epf->func_no,
> @@ -557,14 +569,14 @@ static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
> return ret;
>
> err_alloc_peer_mem:
> - pci_epc_mem_free_addr(ntb->epf->epc, epf_bar->phys_addr,
> mw_addr, epf_bar->size);
> + pci_epf_free_space(ntb->epf, mw_addr, barno, 0);
> return -1;
> }
>
> /**
> * epf_ntb_db_bar_clear() - Clear doorbell BAR and free memory
> * allocated in peer's outbound address space
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> */
> static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
> {
> @@ -580,8 +592,9 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
>
> /**
> * epf_ntb_mw_bar_init() - Configure Memory window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
> {
> @@ -629,7 +642,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
>
> /**
> * epf_ntb_mw_bar_clear() - Clear Memory window BARs
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> */
> static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb)
> {
> @@ -652,7 +665,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb
> *ntb)
>
> /**
> * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> *
> * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB
> interfaces
> */
> @@ -665,7 +678,9 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
> /**
> * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
> * constructs (scratchpad region, doorbell, memorywindow)
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
> {
> @@ -706,11 +721,13 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
>
> /**
> * epf_ntb_epc_init() - Initialize NTB interface
> - * @ntb: NTB device that facilitates communication between HOST and
> vHOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> *
> * Wrapper to initialize a particular EPC interface and start the workqueue
> - * to check for commands from host. This function will write to the
> + * to check for commands from HOST. This function will write to the
> * EP controller HW for configuring it.
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_epc_init(struct epf_ntb *ntb)
> {
> @@ -777,7 +794,7 @@ static int epf_ntb_epc_init(struct epf_ntb *ntb)
>
> /**
> * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
> - * @ntb: NTB device that facilitates communication between HOST1 and
> HOST2
> + * @ntb: NTB device that facilitates communication between HOST and
> VHOST
> *
> * Wrapper to cleanup all NTB interfaces.
> */
> @@ -934,6 +951,8 @@ static const struct config_item_type ntb_group_type
> = {
> *
> * Add configfs directory specific to NTB. This directory will hold
> * NTB specific properties like db_count, spad_count, num_mws etc.,
> + *
> + * Returns: Pointer to config_group
> */
> static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
> struct config_group *group)
> @@ -1084,11 +1103,11 @@ static int vntb_epf_link_enable(struct ntb_dev
> *ntb,
> static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
> {
> struct epf_ntb *ntb = ntb_ndev(ndev);
> - int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * 4;
> + int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count *
> sizeof(u32);
> u32 val;
> - void __iomem *base = ntb->reg;
> + void __iomem *base = (void __iomem *)ntb->reg;
>
> - val = readl(base + off + ct + idx * 4);
> + val = readl(base + off + ct + idx * sizeof(u32));
> return val;
> }
>
> @@ -1096,10 +1115,10 @@ static int vntb_epf_spad_write(struct ntb_dev
> *ndev, int idx, u32 val)
> {
> struct epf_ntb *ntb = ntb_ndev(ndev);
> struct epf_ntb_ctrl *ctrl = ntb->reg;
> - int off = ctrl->spad_offset, ct = ctrl->spad_count * 4;
> - void __iomem *base = ntb->reg;
> + int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
> + void __iomem *base = (void __iomem *)ntb->reg;
>
> - writel(val, base + off + ct + idx * 4);
> + writel(val, base + off + ct + idx * sizeof(u32));
> return 0;
> }
>
> @@ -1108,10 +1127,10 @@ static u32 vntb_epf_peer_spad_read(struct
> ntb_dev *ndev, int pidx, int idx)
> struct epf_ntb *ntb = ntb_ndev(ndev);
> struct epf_ntb_ctrl *ctrl = ntb->reg;
> int off = ctrl->spad_offset;
> - void __iomem *base = ntb->reg;
> + void __iomem *base = (void __iomem *)ntb->reg;
> u32 val;
>
> - val = readl(base + off + idx * 4);
> + val = readl(base + off + idx * sizeof(u32));
> return val;
> }
>
> @@ -1120,9 +1139,9 @@ static int vntb_epf_peer_spad_write(struct
> ntb_dev *ndev, int pidx, int idx, u32
> struct epf_ntb *ntb = ntb_ndev(ndev);
> struct epf_ntb_ctrl *ctrl = ntb->reg;
> int off = ctrl->spad_offset;
> - void __iomem *base = ntb->reg;
> + void __iomem *base = (void __iomem *)ntb->reg;
>
> - writel(val, base + off + idx * 4);
> + writel(val, base + off + idx * sizeof(u32));
> return 0;
> }
>
> @@ -1275,6 +1294,8 @@ static struct pci_driver vntb_pci_driver = {
> * Invoked when a primary interface or secondary interface is bound to EPC
> * device. This function will succeed only when EPC is bound to both the
> * interfaces.
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_bind(struct pci_epf *epf)
> {
> @@ -1359,6 +1380,8 @@ static struct pci_epf_ops epf_ntb_ops = {
> *
> * Probe NTB function driver when endpoint function bus detects a NTB
> * endpoint function.
> + *
> + * Returns: Zero for success, or an error code in case of failure
> */
> static int epf_ntb_probe(struct pci_epf *epf)
> {
> --
> 2.35.1