Hi Mathieu, On 07/09/22 00:58, Mathieu Poirier wrote: > On Fri, Sep 02, 2022 at 03:09:04PM +0530, Md Danish Anwar wrote: >> Hi Mathieu, >> >> >> On 15/07/22 11:52, Kishon Vijay Abraham I wrote: >>> +Danish >>> >>> Hi Mathieu, >>> >>> On 14/07/22 22:50, Mathieu Poirier wrote: >>>> On Tue, Jul 12, 2022 at 11:59:49AM -0600, Mathieu Poirier wrote: >>>>> Hi Puranjay, >>> >>> Removed Puranjay (as he is no longer with TI) and adding Danish. >>> >>> Regards, >>> Kishon >>>>> >>>>> On Tue, Jun 07, 2022 at 10:26:46AM +0530, Puranjay Mohan wrote: >>>>>> From: Tero Kristo <t-kristo@xxxxxx> >>>>>> >>>>>> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU >>>>>> driver to allow client drivers to acquire and release the remoteproc >>>>>> device associated with a PRU core. The PRU cores are treated as >>>>>> resources with only one client owning it at a time. >>>>>> >>>>>> The pru_rproc_get() function returns the rproc handle corresponding >>>>>> to a PRU core identified by the device tree "ti,prus" property under >>>>>> the client node. The pru_rproc_put() is the complementary function >>>>>> to pru_rproc_get(). >>>>>> >>>>>> Co-developed-by: Suman Anna <s-anna@xxxxxx> >>>>>> Signed-off-by: Suman Anna <s-anna@xxxxxx> >>>>>> Signed-off-by: Tero Kristo <t-kristo@xxxxxx> >>>>>> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@xxxxxxxxxx> >>>>>> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@xxxxxxxxxx> >>>>>> Co-developed-by: Puranjay Mohan <p-mohan@xxxxxx> >>>>>> Signed-off-by: Puranjay Mohan <p-mohan@xxxxxx> >>>>>> --- >>>>>> drivers/remoteproc/pru_rproc.c | 138 +++++++++++++++++++++++++++++++-- >>>>>> include/linux/pruss.h | 56 +++++++++++++ >>>>>> 2 files changed, 189 insertions(+), 5 deletions(-) >>>>>> create mode 100644 include/linux/pruss.h >>>>>> >>>>>> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c >>>>>> index 1777a01fa84e..7a35b400287a 100644 >>>>>> --- a/drivers/remoteproc/pru_rproc.c >>>>>> +++ b/drivers/remoteproc/pru_rproc.c >>>>>> @@ -2,12 +2,13 @@ >>>>>> /* >>>>>> * PRU-ICSS remoteproc driver for various TI SoCs >>>>>> * >>>>>> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/ >>>>>> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/ >>>>>> * >>>>>> * Author(s): >>>>>> * Suman Anna <s-anna@xxxxxx> >>>>>> * Andrew F. Davis <afd@xxxxxx> >>>>>> * Grzegorz Jaszczyk <grzegorz.jaszczyk@xxxxxxxxxx> for Texas Instruments >>>>>> + * Puranjay Mohan <p-mohan@xxxxxx> >>>>>> */ >>>>>> #include <linux/bitops.h> >>>>>> @@ -16,6 +17,7 @@ >>>>>> #include <linux/module.h> >>>>>> #include <linux/of_device.h> >>>>>> #include <linux/of_irq.h> >>>>>> +#include <linux/pruss.h> >>>>>> #include <linux/pruss_driver.h> >>>>>> #include <linux/remoteproc.h> >>>>>> @@ -111,6 +113,8 @@ struct pru_private_data { >>>>>> * @rproc: remoteproc pointer for this PRU core >>>>>> * @data: PRU core specific data >>>>>> * @mem_regions: data for each of the PRU memory regions >>>>>> + * @client_np: client device node >>>>>> + * @lock: mutex to protect client usage >>>>>> * @fw_name: name of firmware image used during loading >>>>>> * @mapped_irq: virtual interrupt numbers of created fw specific mapping >>>>>> * @pru_interrupt_map: pointer to interrupt mapping description (firmware) >>>>>> @@ -126,6 +130,8 @@ struct pru_rproc { >>>>>> struct rproc *rproc; >>>>>> const struct pru_private_data *data; >>>>>> struct pruss_mem_region mem_regions[PRU_IOMEM_MAX]; >>>>>> + struct device_node *client_np; >>>>>> + struct mutex lock; /* client access lock */ >>>>>> const char *fw_name; >>>>>> unsigned int *mapped_irq; >>>>>> struct pru_irq_rsc *pru_interrupt_map; >>>>>> @@ -146,6 +152,125 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val) >>>>>> writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg); >>>>>> } >>>>>> +static struct rproc *__pru_rproc_get(struct device_node *np, int index) >>>>>> +{ >>>>>> + struct device_node *rproc_np = NULL; >>>>>> + struct platform_device *pdev; >>>>>> + struct rproc *rproc; >>>>>> + >>>>>> + rproc_np = of_parse_phandle(np, "ti,prus", index); >>>>>> + if (!rproc_np || !of_device_is_available(rproc_np)) >>>>>> + return ERR_PTR(-ENODEV); >>>>>> + >>>>>> + pdev = of_find_device_by_node(rproc_np); >>>>>> + of_node_put(rproc_np); >>>>>> + >>>>>> + if (!pdev || !(&pdev->dev) || !((&pdev->dev)->driver)) >>>>>> + /* probably PRU not yet probed */ >>>>>> + return ERR_PTR(-EPROBE_DEFER); >>>>>> + >>>>>> + /* make sure it is PRU rproc */ >>>>>> + if (!is_pru_rproc(&pdev->dev)) { >>>>>> + put_device(&pdev->dev); >>>>>> + return ERR_PTR(-ENODEV); >>>>>> + } >>>>>> + >>>>>> + rproc = platform_get_drvdata(pdev); >>>>>> + put_device(&pdev->dev); >>>>>> + if (!rproc) >>>>>> + return ERR_PTR(-EPROBE_DEFER); >>>>>> + >>>>>> + get_device(&rproc->dev); >>>>>> + >>>>>> + return rproc; >>>>>> +} >>>>>> + >>>>>> +/** >>>>>> + * pru_rproc_get() - get the PRU rproc instance from a device node >>>>>> + * @np: the user/client device node >>>>>> + * @index: index to use for the ti,prus property >>>>>> + * @pru_id: optional pointer to return the PRU remoteproc processor id >>>>>> + * >>>>>> + * This function looks through a client device node's "ti,prus" property at >>>>>> + * index @index and returns the rproc handle for a valid PRU remote processor if >>>>>> + * found. The function allows only one user to own the PRU rproc resource at a >>>>>> + * time. Caller must call pru_rproc_put() when done with using the rproc, not >>>>>> + * required if the function returns a failure. >>>>>> + * >>>>>> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is >>>>>> + * returned. >>>>>> + * >>>>>> + * Return: rproc handle on success, and an ERR_PTR on failure using one >>>>>> + * of the following error values >>>>>> + * -ENODEV if device is not found >>>>>> + * -EBUSY if PRU is already acquired by anyone >>>>>> + * -EPROBE_DEFER is PRU device is not probed yet >>>>>> + */ >>>>>> +struct rproc *pru_rproc_get(struct device_node *np, int index, >>>>>> + enum pruss_pru_id *pru_id) >>>>>> +{ >>>>>> + struct rproc *rproc; >>>>>> + struct pru_rproc *pru; >>>>>> + struct device *dev; >>>>>> + >>>>>> + try_module_get(THIS_MODULE); >>>>> >>>>> There should be a module_put() in pru_rproc_put()... >>>> >>>> ... and in the error path of this function. >>>> >>>>> >>>>> More comments to come tomorrow. I'm especially worried about this API racing >>>>> with a remote processor being removed or detached. >>>>> >>>> >>>> Looking at what is done in wkup_m3_ipc_probe(), it should be possible to call >>>> rproc_get_by_handle() here and that would make sure the remote processor doesn't >>>> go away before the end of the function. >>>> >>>> More comments to come... >> >> It is possible to call rproc_get_by_handle() here instead of >> __pru_get_proc(), but that would not provide multiple functionality. >> >> The API rproc_get_by_handle() returns rproc handle on success, and NULL on >> failure where as __pru_get_proc() returns ERR_PTR on failure which provides >> multiple functionality and opportunity for us to distinguish between >> multiple errors. >> >> So we have these three options. >> >> 1. If we're using the API rproc_get_by_handle() and we want the multiple >> ERR_PTR on failure then we will need to change the API rproc_get_by_handle() >> and also all the functions that uses rproc_get_by_handle(). >> > > Not optimal. > >> 2. Keep the API rproc_get_by_handle() as it is. That will restrict us from >> using multiple ERR_PTR on different kinds of error. >> > > Not optimal. > >> 3. Instead of using rproc_get_by_handle(), keep using __pru_get_proc(). This >> will make sure we have the proper ERR_PTR to retrun for different kinds of >> errors. >> > > Unacceptable for the reason I already stated. > >> Please let me know which option to continue with. > > I suggest building a wrapper that does everything you want around rproc_get_by_phandle(). > Sure, I'll do that. I'll share this change in v6 of this patch series. >> >> Thanks, >> Danish >> >> >>>> >>>> >>>>> Thanks, >>>>> Mathieu >>>>> >>>>>> + >>>>>> + rproc = __pru_rproc_get(np, index); >>>>>> + if (IS_ERR(rproc)) >>>>>> + return rproc; >>>>>> + >>>>>> + pru = rproc->priv; >>>>>> + dev = &rproc->dev; >>>>>> + >>>>>> + mutex_lock(&pru->lock); >>>>>> + >>>>>> + if (pru->client_np) { >>>>>> + mutex_unlock(&pru->lock); >>>>>> + put_device(dev); >>>>>> + return ERR_PTR(-EBUSY); >>>>>> + } >>>>>> + >>>>>> + pru->client_np = np; >>>>>> + >>>>>> + mutex_unlock(&pru->lock); >>>>>> + >>>>>> + if (pru_id) >>>>>> + *pru_id = pru->id; >>>>>> + >>>>>> + return rproc; >>>>>> +} >>>>>> +EXPORT_SYMBOL_GPL(pru_rproc_get); >>>>>> + >>>>>> +/** >>>>>> + * pru_rproc_put() - release the PRU rproc resource >>>>>> + * @rproc: the rproc resource to release >>>>>> + * >>>>>> + * Releases the PRU rproc resource and makes it available to other >>>>>> + * users. >>>>>> + */ >>>>>> +void pru_rproc_put(struct rproc *rproc) >>>>>> +{ >>>>>> + struct pru_rproc *pru; >>>>>> + >>>>>> + if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent)) >>>>>> + return; >>>>>> + >>>>>> + pru = rproc->priv; >>>>>> + >>>>>> + mutex_lock(&pru->lock); >>>>>> + >>>>>> + if (!pru->client_np) { >>>>>> + mutex_unlock(&pru->lock); >>>>>> + return; >>>>>> + } >>>>>> + >>>>>> + pru->client_np = NULL; >>>>>> + mutex_unlock(&pru->lock); >>>>>> + >>>>>> + put_device(&rproc->dev); >>>>>> +} >>>>>> +EXPORT_SYMBOL_GPL(pru_rproc_put); >>>>>> + >>>>>> static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg) >>>>>> { >>>>>> return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg); >>>>>> @@ -438,7 +563,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len) >>>>>> dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0]; >>>>>> dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1]; >>>>>> /* PRU1 has its local RAM addresses reversed */ >>>>>> - if (pru->id == 1) >>>>>> + if (pru->id == PRUSS_PRU1) >>>>>> swap(dram0, dram1); >>>>>> shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2]; >>>>>> @@ -747,14 +872,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru) >>>>>> case RTU0_IRAM_ADDR_MASK: >>>>>> fallthrough; >>>>>> case PRU0_IRAM_ADDR_MASK: >>>>>> - pru->id = 0; >>>>>> + pru->id = PRUSS_PRU0; >>>>>> break; >>>>>> case TX_PRU1_IRAM_ADDR_MASK: >>>>>> fallthrough; >>>>>> case RTU1_IRAM_ADDR_MASK: >>>>>> fallthrough; >>>>>> case PRU1_IRAM_ADDR_MASK: >>>>>> - pru->id = 1; >>>>>> + pru->id = PRUSS_PRU1; >>>>>> break; >>>>>> default: >>>>>> ret = -EINVAL; >>>>>> @@ -816,6 +941,8 @@ static int pru_rproc_probe(struct platform_device *pdev) >>>>>> pru->pruss = platform_get_drvdata(ppdev); >>>>>> pru->rproc = rproc; >>>>>> pru->fw_name = fw_name; >>>>>> + pru->client_np = NULL; >>>>>> + mutex_init(&pru->lock); >>>>>> for (i = 0; i < ARRAY_SIZE(mem_names); i++) { >>>>>> res = platform_get_resource_byname(pdev, IORESOURCE_MEM, >>>>>> @@ -903,7 +1030,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match); >>>>>> static struct platform_driver pru_rproc_driver = { >>>>>> .driver = { >>>>>> - .name = "pru-rproc", >>>>>> + .name = PRU_RPROC_DRVNAME, >>>>>> .of_match_table = pru_rproc_match, >>>>>> .suppress_bind_attrs = true, >>>>>> }, >>>>>> @@ -915,5 +1042,6 @@ module_platform_driver(pru_rproc_driver); >>>>>> MODULE_AUTHOR("Suman Anna <s-anna@xxxxxx>"); >>>>>> MODULE_AUTHOR("Andrew F. Davis <afd@xxxxxx>"); >>>>>> MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@xxxxxxxxxx>"); >>>>>> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@xxxxxx>"); >>>>>> MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver"); >>>>>> MODULE_LICENSE("GPL v2"); >>>>>> diff --git a/include/linux/pruss.h b/include/linux/pruss.h >>>>>> new file mode 100644 >>>>>> index 000000000000..fdc719b43db0 >>>>>> --- /dev/null >>>>>> +++ b/include/linux/pruss.h >>>>>> @@ -0,0 +1,56 @@ >>>>>> +/* SPDX-License-Identifier: GPL-2.0-only */ >>>>>> +/** >>>>>> + * PRU-ICSS Subsystem user interfaces >>>>>> + * >>>>>> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com >>>>>> + * Suman Anna <s-anna@xxxxxx> >>>>>> + */ >>>>>> + >>>>>> +#ifndef __LINUX_PRUSS_H >>>>>> +#define __LINUX_PRUSS_H >>>>>> + >>>>>> +#include <linux/device.h> >>>>>> +#include <linux/types.h> >>>>>> + >>>>>> +#define PRU_RPROC_DRVNAME "pru-rproc" >>>>>> + >>>>>> +/* >>>>>> + * enum pruss_pru_id - PRU core identifiers >>>>>> + */ >>>>>> +enum pruss_pru_id { >>>>>> + PRUSS_PRU0 = 0, >>>>>> + PRUSS_PRU1, >>>>>> + PRUSS_NUM_PRUS, >>>>>> +}; >>>>>> + >>>>>> +struct device_node; >>>>>> + >>>>>> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC) >>>>>> + >>>>>> +struct rproc *pru_rproc_get(struct device_node *np, int index, >>>>>> + enum pruss_pru_id *pru_id); >>>>>> +void pru_rproc_put(struct rproc *rproc); >>>>>> + >>>>>> +#else >>>>>> + >>>>>> +static inline struct rproc * >>>>>> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id) >>>>>> +{ >>>>>> + return ERR_PTR(-EOPNOTSUPP); >>>>>> +} >>>>>> + >>>>>> +static inline void pru_rproc_put(struct rproc *rproc) { } >>>>>> + >>>>>> +#endif /* CONFIG_PRU_REMOTEPROC */ >>>>>> + >>>>>> +static inline bool is_pru_rproc(struct device *dev) >>>>>> +{ >>>>>> + const char *drv_name = dev_driver_string(dev); >>>>>> + >>>>>> + if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME))) >>>>>> + return false; >>>>>> + >>>>>> + return true; >>>>>> +} >>>>>> + >>>>>> +#endif /* __LINUX_PRUSS_H */ >>>>>> -- >>>>>> 2.17.1 >>>>>>
