From: "Andrew F. Davis" <[email protected]> Add two new API - pruss_request_mem_region() & pruss_release_mem_region(), to the PRUSS platform driver to allow client drivers to acquire and release the common memory resources present within a PRU-ICSS subsystem. This allows the client drivers to directly manipulate the respective memories, as per their design contract with the associated firmware.
Signed-off-by: Andrew F. Davis <[email protected]> [[email protected]: rename functions, add error checking, comments] Signed-off-by: Suman Anna <[email protected]> Signed-off-by: Roger Quadros <[email protected]> --- drivers/soc/ti/pruss.c | 81 +++++++++++++++++++++++++++++++++++++++++++++ drivers/soc/ti/pruss.h | 26 +++------------ drivers/soc/ti/pruss_intc.c | 1 + include/linux/pruss.h | 61 ++++++++++++++++++++++++++++++++++ 4 files changed, 147 insertions(+), 22 deletions(-) create mode 100644 include/linux/pruss.h diff --git a/drivers/soc/ti/pruss.c b/drivers/soc/ti/pruss.c index 0840b59..c2271c4 100644 --- a/drivers/soc/ti/pruss.c +++ b/drivers/soc/ti/pruss.c @@ -12,9 +12,89 @@ #include <linux/io.h> #include <linux/of_address.h> #include <linux/of_device.h> +#include <linux/pruss.h> #include "pruss.h" +/** + * pruss_request_mem_region() - request a memory resource + * @pruss: the pruss instance + * @mem_id: the memory resource id + * @region: pointer to memory region structure to be filled in + * + * This function allows a client driver to request a memory resource, + * and if successful, will let the client driver own the particular + * memory region until released using the pruss_release_mem_region() + * API. + * + * Returns the memory region if requested resource is available, an + * error otherwise + */ +int pruss_request_mem_region(struct pruss *pruss, enum pruss_mem mem_id, + struct pruss_mem_region *region) +{ + if (!pruss || !region) + return -EINVAL; + + if (mem_id >= PRUSS_MEM_MAX) + return -EINVAL; + + mutex_lock(&pruss->lock); + + if (pruss->mem_in_use[mem_id]) { + mutex_unlock(&pruss->lock); + return -EBUSY; + } + + *region = pruss->mem_regions[mem_id]; + pruss->mem_in_use[mem_id] = region; + + mutex_unlock(&pruss->lock); + + return 0; +} +EXPORT_SYMBOL_GPL(pruss_request_mem_region); + +/** + * pruss_release_mem_region() - release a memory resource + * @pruss: the pruss instance + * @region: the memory region to release + * + * This function is the complimentary function to + * pruss_request_mem_region(), and allows the client drivers to + * release back a memory resource. + * + * Returns 0 on success, an error code otherwise + */ +int pruss_release_mem_region(struct pruss *pruss, + struct pruss_mem_region *region) +{ + int id; + + if (!pruss || !region) + return -EINVAL; + + mutex_lock(&pruss->lock); + + /* find out the memory region being released */ + for (id = 0; id < PRUSS_MEM_MAX; id++) { + if (pruss->mem_in_use[id] == region) + break; + } + + if (id == PRUSS_MEM_MAX) { + mutex_unlock(&pruss->lock); + return -EINVAL; + } + + pruss->mem_in_use[id] = NULL; + + mutex_unlock(&pruss->lock); + + return 0; +} +EXPORT_SYMBOL_GPL(pruss_release_mem_region); + static int pruss_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -41,6 +121,7 @@ static int pruss_probe(struct platform_device *pdev) return -ENOMEM; pruss->dev = dev; + mutex_init(&pruss->lock); np = of_get_child_by_name(node, "memories"); if (!np) diff --git a/drivers/soc/ti/pruss.h b/drivers/soc/ti/pruss.h index a5a0667..f8878c2 100644 --- a/drivers/soc/ti/pruss.h +++ b/drivers/soc/ti/pruss.h @@ -22,28 +22,6 @@ #define MAX_PRU_HOST_INT 10 /** - * enum pruss_mem - PRUSS memory range identifiers - */ -enum pruss_mem { - PRUSS_MEM_DRAM0 = 0, - PRUSS_MEM_DRAM1, - PRUSS_MEM_SHRD_RAM2, - PRUSS_MEM_MAX, -}; - -/** - * struct pruss_mem_region - PRUSS memory region structure - * @va: kernel virtual address of the PRUSS memory region - * @pa: physical (bus) address of the PRUSS memory region - * @size: size of the PRUSS memory region - */ -struct pruss_mem_region { - void __iomem *va; - phys_addr_t pa; - size_t size; -}; - -/** * struct pruss_intc_config - INTC configuration info * @sysev_to_ch: system events to channel mapping information * @ch_to_host: interrupt channel to host interrupt information @@ -57,12 +35,16 @@ struct pruss_intc_config { * struct pruss - PRUSS parent structure * @dev: pruss device pointer * @mem_regions: data for each of the PRUSS memory regions + * @mem_in_use: to indicate if memory resource is in use * @host_mask: indicate which HOST IRQs are enabled + * @lock: mutex to serialize access to resources */ struct pruss { struct device *dev; struct pruss_mem_region mem_regions[PRUSS_MEM_MAX]; + struct pruss_mem_region *mem_in_use[PRUSS_MEM_MAX]; u32 host_mask; + struct mutex lock; /* PRU resource lock */ }; int pruss_intc_configure(struct pruss *pruss, diff --git a/drivers/soc/ti/pruss_intc.c b/drivers/soc/ti/pruss_intc.c index dde054b..df6b83b 100644 --- a/drivers/soc/ti/pruss_intc.c +++ b/drivers/soc/ti/pruss_intc.c @@ -13,6 +13,7 @@ #include <linux/module.h> #include <linux/of_device.h> #include <linux/platform_device.h> +#include <linux/pruss.h> #include "pruss.h" diff --git a/include/linux/pruss.h b/include/linux/pruss.h new file mode 100644 index 0000000..198ae25 --- /dev/null +++ b/include/linux/pruss.h @@ -0,0 +1,61 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/** + * PRU-ICSS Subsystem user interfaces + * + * Copyright (C) 2015-2018 Texas Instruments Incorporated - http://www.ti.com + * Suman Anna <[email protected]> + * Tero Kristo <[email protected]> + */ + +#ifndef __LINUX_PRUSS_H +#define __LINUX_PRUSS_H + +/** + * enum pruss_mem - PRUSS memory range identifiers + */ +enum pruss_mem { + PRUSS_MEM_DRAM0 = 0, + PRUSS_MEM_DRAM1, + PRUSS_MEM_SHRD_RAM2, + PRUSS_MEM_MAX, +}; + +/** + * struct pruss_mem_region - PRUSS memory region structure + * @va: kernel virtual address of the PRUSS memory region + * @pa: physical (bus) address of the PRUSS memory region + * @size: size of the PRUSS memory region + */ +struct pruss_mem_region { + void __iomem *va; + phys_addr_t pa; + size_t size; +}; + +struct pruss; + +#if IS_ENABLED(CONFIG_TI_PRUSS) + +int pruss_request_mem_region(struct pruss *pruss, enum pruss_mem mem_id, + struct pruss_mem_region *region); +int pruss_release_mem_region(struct pruss *pruss, + struct pruss_mem_region *region); + +#else + +static inline int pruss_request_mem_region(struct pruss *pruss, + enum pruss_mem mem_id, + struct pruss_mem_region *region) +{ + return -ENOTSUPP; +} + +static inline int pruss_release_mem_region(struct pruss *pruss, + struct pruss_mem_region *region) +{ + return -ENOTSUPP; +} + +#endif /* CONFIG_TI_PRUSS */ + +#endif /* __LINUX_PRUSS_H */ -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
