On 08/11/2022 12:08, Md Danish Anwar wrote: > Hi Roger, > > On 04/11/22 18:25, Roger Quadros wrote: >> Hi Danish, >> >> On 31/10/2022 09:37, MD Danish Anwar 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> >>> Signed-off-by: MD Danish Anwar <danishanwar@xxxxxx> >>> --- >>> drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++-- >>> include/linux/pruss.h | 56 +++++++++++++ >>> 2 files changed, 193 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 128bf9912f2c..9ba73cfc29e2 100644 >>> --- a/drivers/remoteproc/pru_rproc.c >>> +++ b/drivers/remoteproc/pru_rproc.c >>> @@ -2,12 +2,14 @@ >>> /* >>> * 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> >>> + * Md Danish Anwar <danishanwar@xxxxxx> >>> */ >>> >>> #include <linux/bitops.h> >>> @@ -16,6 +18,7 @@ >>> #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 +114,8 @@ 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 +131,8 @@ 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 +153,127 @@ 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 rproc *rproc; >>> + phandle rproc_phandle; >>> + int ret; >>> + >>> + ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle); >>> + if (ret) >>> + return ERR_PTR(ret); >>> + >>> + rproc = rproc_get_by_phandle(rproc_phandle); >>> + if (!rproc) { >>> + ret = -EPROBE_DEFER; >>> + goto err_no_rproc_handle; >>> + } >>> + >>> + /* make sure it is PRU rproc */ >>> + if (!is_pru_rproc(rproc->dev.parent)) { >>> + rproc_put(rproc); >>> + return ERR_PTR(-ENODEV); >>> + } >>> + >>> + get_device(&rproc->dev); >> >> Why do you need a get_device() here? >> rproc_get_by_phandle() does it right? >> > > Yes, this get_device() is not required. I'll remove it. > >>> + >>> + return rproc; >>> + >>> +err_no_rproc_handle: >>> + rproc_put(rproc); >>> + return ERR_PTR(ret); >>> +} >>> + >>> +/** >>> + * 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; >>> + int ret; >>> + >>> + rproc = __pru_rproc_get(np, index); >>> + if (IS_ERR(rproc)) >>> + return rproc; >> >> Why bother doing __pru_rproc_get() if pru->client_np exists? >> >> You could do the below if check first and exit if pru->client_np exists. >> > > In order to do the below if check, we need to have pru. pru is obtained from > rproc->priv and rproc is obtained from __pru_rproc_get() API. So in order to > run the below if check we need to call the __pru_rproc_get() API first. > > So, first we are obtaining rproc from __pru_rproc_get() API and then checking > and exiting if pru->client_np exists. Indeed. sorry for the noise. > >>> + >>> + pru = rproc->priv; >>> + dev = &rproc->dev; >>> + >>> + mutex_lock(&pru->lock); >>> + >>> + if (pru->client_np) { >>> + mutex_unlock(&pru->lock); >>> + put_device(dev); >>> + ret = -EBUSY; >>> + goto err_no_rproc_handle; >>> + } >>> + >>> + pru->client_np = np; >>> + >>> + mutex_unlock(&pru->lock); >>> + >>> + if (pru_id) >>> + *pru_id = pru->id; >>> + >>> + return rproc; >>> + >>> +err_no_rproc_handle: >>> + rproc_put(rproc); >>> + return ERR_PTR(ret); >>> +} >>> +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); >>> + >>> + rproc_put(rproc); >>> +} >>> +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 +566,7 @@ 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) >> >> Introduction of PRUSS_PRU0/1 enum could have been a separate patch. >> >>> swap(dram0, dram1); >>> shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2]; >>> >>> @@ -747,14 +875,14 @@ 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 +944,8 @@ 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, >>> @@ -904,7 +1034,7 @@ 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, >>> }, >>> @@ -916,5 +1046,7 @@ 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_AUTHOR("Md Danish Anwar <danishanwar@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 */ >> >> cheers, >> -roger > > Thanks and Regards, > Danish. cheers, -roger
