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[68.147.0.187]) by smtp.gmail.com with ESMTPSA id s70sm3311160pfc.97.2020.12.04.09.40.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Dec 2020 09:40:18 -0800 (PST) Date: Fri, 4 Dec 2020 10:40:16 -0700 From: Mathieu Poirier To: Grzegorz Jaszczyk Subject: Re: [PATCH v2 3/6] remoteproc/pru: Add support for PRU specific interrupt configuration Message-ID: <20201204174016.GD1392978@xps15> References: <20201119140850.12268-1-grzegorz.jaszczyk@linaro.org> <20201119140850.12268-4-grzegorz.jaszczyk@linaro.org> <20201202225739.GF1282360@xps15> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201204_124022_804653_84199DF8 X-CRM114-Status: GOOD ( 50.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ohad Ben Cohen , devicetree@vger.kernel.org, linux-omap@vger.kernel.org, "Bajjuri, Praneeth" , linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, Bjorn Andersson , Rob Herring , Lee Jones , linux-arm-kernel@lists.infradead.org, Roger Quadros Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Dec 04, 2020 at 03:11:55PM +0100, Grzegorz Jaszczyk wrote: > Hi Mathieu, > > On Wed, 2 Dec 2020 at 23:57, Mathieu Poirier wrote: > > > > On Thu, Nov 19, 2020 at 03:08:47PM +0100, Grzegorz Jaszczyk wrote: > > > The firmware blob can contain optional ELF sections: .resource_table > > > section and .pru_irq_map one. The second one contains the PRUSS > > > interrupt mapping description, which needs to be setup before powering > > > on the PRU core. To avoid RAM wastage this ELF section is not mapped to > > > any ELF segment (by the firmware linker) and therefore is not loaded to > > > PRU memory. > > > > > > The PRU interrupt configuration is handled within the PRUSS INTC irqchip > > > driver and leverages the system events to interrupt channels and host > > > interrupts mapping configuration. Relevant irq routing information is > > > passed through a special .pru_irq_map ELF section (for interrupts routed > > > to and used by PRU cores) or via the PRU application's device tree node > > > (for interrupts routed to and used by the main CPU). The mappings are > > > currently programmed during the booting/shutdown of the PRU. > > > > > > The interrupt configuration passed through .pru_irq_map ELF section is > > > optional. It varies on specific firmware functionality and therefore > > > have to be unwinded during PRU stop and performed again during > > > PRU start. > > > > > > Co-developed-by: Suman Anna > > > Signed-off-by: Suman Anna > > > Signed-off-by: Grzegorz Jaszczyk > > > --- > > > v1->v2: > > > Address Suman comments: > > > - Rework pru_rproc_find_interrupt_map() style: get rid of generic ELF > > > helpers macros usage and stick with elf32_* related structs instead > > > (in order to be consistent with pru_rproc_load_elf_segments() style). > > > - Improve comments and dev_err msgs in pru_rproc_find_interrupt_map(). > > > - Use u8 instead of ssize_t for evt_count. > > > --- > > > drivers/remoteproc/pru_rproc.c | 180 +++++++++++++++++++++++++++++++++ > > > drivers/remoteproc/pru_rproc.h | 46 +++++++++ > > > 2 files changed, 226 insertions(+) > > > create mode 100644 drivers/remoteproc/pru_rproc.h > > > > > > diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c > > > index b686f19f9b1a..c68c3d6bfddd 100644 > > > --- a/drivers/remoteproc/pru_rproc.c > > > +++ b/drivers/remoteproc/pru_rproc.c > > > @@ -11,13 +11,16 @@ > > > */ > > > > > > #include > > > +#include > > > #include > > > #include > > > +#include > > > #include > > > #include > > > > > > #include "remoteproc_internal.h" > > > #include "remoteproc_elf_helpers.h" > > > +#include "pru_rproc.h" > > > > > > /* PRU_ICSS_PRU_CTRL registers */ > > > #define PRU_CTRL_CTRL 0x0000 > > > @@ -42,6 +45,8 @@ > > > #define PRU_SDRAM_DA 0x2000 /* Secondary Data RAM */ > > > #define PRU_SHRDRAM_DA 0x10000 /* Shared Data RAM */ > > > > > > +#define MAX_PRU_SYS_EVENTS 160 > > > + > > > /** > > > * enum pru_iomem - PRU core memory/register range identifiers > > > * > > > @@ -65,6 +70,10 @@ enum pru_iomem { > > > * @rproc: remoteproc pointer for this PRU core > > > * @mem_regions: data for each of the PRU memory regions > > > * @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) > > > + * @pru_interrupt_map_sz: pru_interrupt_map size > > > + * @evt_count: number of mapped events > > > */ > > > struct pru_rproc { > > > int id; > > > @@ -73,6 +82,10 @@ struct pru_rproc { > > > struct rproc *rproc; > > > struct pruss_mem_region mem_regions[PRU_IOMEM_MAX]; > > > const char *fw_name; > > > + int *mapped_irq; > > > + struct pru_irq_rsc *pru_interrupt_map; > > > + size_t pru_interrupt_map_sz; > > > + u8 evt_count; > > > }; > > > > > > static inline u32 pru_control_read_reg(struct pru_rproc *pru, unsigned int reg) > > > @@ -86,15 +99,107 @@ 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 void pru_dispose_irq_mapping(struct pru_rproc *pru) > > > +{ > > > + while (pru->evt_count--) { > > > + if (pru->mapped_irq[pru->evt_count] > 0) > > > + irq_dispose_mapping(pru->mapped_irq[pru->evt_count]); > > > + } > > > + > > > + kfree(pru->mapped_irq); > > > +} > > > + > > > +/* > > > + * Parse the custom PRU interrupt map resource and configure the INTC > > > + * appropriately. > > > + */ > > > +static int pru_handle_intrmap(struct rproc *rproc) > > > +{ > > > + struct device *dev = rproc->dev.parent; > > > + struct pru_rproc *pru = rproc->priv; > > > + struct pru_irq_rsc *rsc = pru->pru_interrupt_map; > > > + struct irq_fwspec fwspec; > > > + struct device_node *irq_parent; > > > + int i, ret = 0; > > > + > > > + /* not having pru_interrupt_map is not an error */ > > > + if (!rsc) > > > + return 0; > > > + > > > + /* currently supporting only type 0 */ > > > + if (rsc->type != 0) { > > > + dev_err(dev, "unsupported rsc type: %d\n", rsc->type); > > > + return -EINVAL; > > > + } > > > + > > > + if (rsc->num_evts < 0 || rsc->num_evts > MAX_PRU_SYS_EVENTS) > > > + return -EINVAL; > > > + > > > > pru_irq_rsc::num_evts is a 'u8' and can't be negative. > > Sure - I will remove the 'rsc->num_evts < 0 ' check. > > > > > > + if (sizeof(*rsc) + rsc->num_evts * sizeof(struct pruss_int_map) != > > > + pru->pru_interrupt_map_sz) > > > + return -EINVAL; > > > + > > > + pru->evt_count = rsc->num_evts; > > > + pru->mapped_irq = kcalloc(pru->evt_count, sizeof(int), GFP_KERNEL); > > > + if (!pru->mapped_irq) > > > + return -ENOMEM; > > > + > > > + /* > > > + * parse and fill in system event to interrupt channel and > > > + * channel-to-host mapping > > > + */ > > > + irq_parent = of_irq_find_parent(pru->dev->of_node); > > > + if (!irq_parent) { > > > + kfree(pru->mapped_irq); > > > + return -ENODEV; > > > + } > > > + > > > + fwspec.fwnode = of_node_to_fwnode(irq_parent); > > > + fwspec.param_count = 3; > > > + for (i = 0; i < pru->evt_count; i++) { > > > + fwspec.param[0] = rsc->pru_intc_map[i].event; > > > + fwspec.param[1] = rsc->pru_intc_map[i].chnl; > > > + fwspec.param[2] = rsc->pru_intc_map[i].host; > > > + > > > + dev_dbg(dev, "mapping%d: event %d, chnl %d, host %d\n", > > > + i, fwspec.param[0], fwspec.param[1], fwspec.param[2]); > > > + > > > + pru->mapped_irq[i] = irq_create_fwspec_mapping(&fwspec); > > > + if (pru->mapped_irq[i] < 0) { > > > > Function irq_create_fwspec_mapping() returns an unsigned int - theoretically the > > above check could return a false positive. I suggest to make > > pru_proc::mapped_irq a '*unsigned int" and revise the error condition. > > You are right - I will do as suggested. > > > > > > + dev_err(dev, "failed to get virq\n"); > > > + ret = pru->mapped_irq[i]; > > > + goto map_fail; > > > + } > > > + } > > > + > > > + return ret; > > > + > > > +map_fail: > > > + pru_dispose_irq_mapping(pru); > > > + > > > + return ret; > > > +} > > > + > > > static int pru_rproc_start(struct rproc *rproc) > > > { > > > struct device *dev = &rproc->dev; > > > struct pru_rproc *pru = rproc->priv; > > > u32 val; > > > + int ret; > > > > > > dev_dbg(dev, "starting PRU%d: entry-point = 0x%llx\n", > > > pru->id, (rproc->bootaddr >> 2)); > > > > > > + ret = pru_handle_intrmap(rproc); > > > + /* > > > + * reset references to pru interrupt map - they will stop being valid > > > + * after rproc_start returns > > > + */ > > > > Why is that? As far as I understand the interrupt map points inside the > > firmware image, which won't go away until @rproc is disposed of or users change > > it via sysfs. And the latter can't happen when the remote processor is active. > > Can't this go to pru_dispose_irq_mapping()? > > Those references are pointing to the fw segments which are released > right after rproc_start() due to release_firmware() call. I think that > resetting them before pru_rproc_start() returns is proper. If you > don't mind I prefer to keep this part as is. You correct - I had rproc::cached_table in mind but that one is kmemdup()'ed. > > Thank you, > Grzegorz > > > > > More comments to come tomorrow. > > > > Thanks, > > Mathieu > > > > > + pru->pru_interrupt_map = NULL; > > > + pru->pru_interrupt_map_sz = 0; > > > + if (ret) > > > + return ret; > > > + > > > val = CTRL_CTRL_EN | ((rproc->bootaddr >> 2) << 16); > > > pru_control_write_reg(pru, PRU_CTRL_CTRL, val); > > > > > > @@ -113,6 +218,10 @@ static int pru_rproc_stop(struct rproc *rproc) > > > val &= ~CTRL_CTRL_EN; > > > pru_control_write_reg(pru, PRU_CTRL_CTRL, val); > > > > > > + /* dispose irq mapping - new firmware can provide new mapping */ > > > + if (pru->mapped_irq) > > > + pru_dispose_irq_mapping(pru); > > > + > > > return 0; > > > } > > > > > > @@ -275,12 +384,70 @@ pru_rproc_load_elf_segments(struct rproc *rproc, const struct firmware *fw) > > > return ret; > > > } > > > > > > +static const void * > > > +pru_rproc_find_interrupt_map(struct device *dev, const struct firmware *fw) > > > +{ > > > + struct elf32_shdr *shdr, *name_table_shdr; > > > + const char *name_table; > > > + const u8 *elf_data = fw->data; > > > + struct elf32_hdr *ehdr = (struct elf32_hdr *)elf_data; > > > + u16 shnum = ehdr->e_shnum; > > > + u16 shstrndx = ehdr->e_shstrndx; > > > + int i; > > > + > > > + /* first, get the section header */ > > > + shdr = (struct elf32_shdr *)(elf_data + ehdr->e_shoff); > > > + /* compute name table section header entry in shdr array */ > > > + name_table_shdr = shdr + shstrndx; > > > + /* finally, compute the name table section address in elf */ > > > + name_table = elf_data + name_table_shdr->sh_offset; > > > + > > > + for (i = 0; i < shnum; i++, shdr++) { > > > + u32 size = shdr->sh_size; > > > + u32 offset = shdr->sh_offset; > > > + u32 name = shdr->sh_name; > > > + > > > + if (strcmp(name_table + name, ".pru_irq_map")) > > > + continue; > > > + > > > + /* make sure we have the entire irq map */ > > > + if (offset + size > fw->size || offset + size < size) { > > > + dev_err(dev, ".pru_irq_map section truncated\n"); > > > + return ERR_PTR(-EINVAL); > > > + } > > > + > > > + /* make sure irq map has at least the header */ > > > + if (sizeof(struct pru_irq_rsc) > size) { > > > + dev_err(dev, "header-less .pru_irq_map section\n"); > > > + return ERR_PTR(-EINVAL); > > > + } > > > + > > > + return shdr; > > > + } > > > + > > > + dev_dbg(dev, "no .pru_irq_map section found for this fw\n"); > > > + > > > + return NULL; > > > +} > > > + > > > /* > > > * Use a custom parse_fw callback function for dealing with PRU firmware > > > * specific sections. > > > + * > > > + * The firmware blob can contain optional ELF sections: .resource_table section > > > + * and .pru_irq_map one. The second one contains the PRUSS interrupt mapping > > > + * description, which needs to be setup before powering on the PRU core. To > > > + * avoid RAM wastage this ELF section is not mapped to any ELF segment (by the > > > + * firmware linker) and therefore is not loaded to PRU memory. > > > */ > > > static int pru_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw) > > > { > > > + struct device *dev = &rproc->dev; > > > + struct pru_rproc *pru = rproc->priv; > > > + const u8 *elf_data = fw->data; > > > + const void *shdr; > > > + u8 class = fw_elf_get_class(fw); > > > + u64 sh_offset; > > > int ret; > > > > > > /* load optional rsc table */ > > > @@ -290,6 +457,19 @@ static int pru_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw) > > > else if (ret) > > > return ret; > > > > > > + /* find .pru_interrupt_map section, not having it is not an error */ > > > + shdr = pru_rproc_find_interrupt_map(dev, fw); > > > + if (IS_ERR(shdr)) > > > + return PTR_ERR(shdr); > > > + > > > + if (!shdr) > > > + return 0; > > > + > > > + /* preserve pointer to PRU interrupt map together with it size */ > > > + sh_offset = elf_shdr_get_sh_offset(class, shdr); > > > + pru->pru_interrupt_map = (struct pru_irq_rsc *)(elf_data + sh_offset); > > > + pru->pru_interrupt_map_sz = elf_shdr_get_sh_size(class, shdr); > > > + > > > return 0; > > > } > > > > > > diff --git a/drivers/remoteproc/pru_rproc.h b/drivers/remoteproc/pru_rproc.h > > > new file mode 100644 > > > index 000000000000..8ee9c3171610 > > > --- /dev/null > > > +++ b/drivers/remoteproc/pru_rproc.h > > > @@ -0,0 +1,46 @@ > > > +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) */ > > > +/* > > > + * PRUSS Remote Processor specific types > > > + * > > > + * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/ > > > + * Suman Anna > > > + */ > > > + > > > +#ifndef _PRU_RPROC_H_ > > > +#define _PRU_RPROC_H_ > > > + > > > +/** > > > + * struct pruss_int_map - PRU system events _to_ channel and host mapping > > > + * @event: number of the system event > > > + * @chnl: channel number assigned to a given @event > > > + * @host: host number assigned to a given @chnl > > > + * > > > + * PRU system events are mapped to channels, and these channels are mapped > > > + * to host interrupts. Events can be mapped to channels in a one-to-one or > > > + * many-to-one ratio (multiple events per channel), and channels can be > > > + * mapped to host interrupts in a one-to-one or many-to-one ratio (multiple > > > + * channels per interrupt). > > > + */ > > > +struct pruss_int_map { > > > + u8 event; > > > + u8 chnl; > > > + u8 host; > > > +}; > > > + > > > +/** > > > + * struct pru_irq_rsc - PRU firmware section header for IRQ data > > > + * @type: resource type > > > + * @num_evts: number of described events > > > + * @pru_intc_map: PRU interrupt routing description > > > + * > > > + * The PRU firmware blob can contain optional .pru_irq_map ELF section, which > > > + * provides the PRUSS interrupt mapping description. The pru_irq_rsc struct > > > + * describes resource entry format. > > > + */ > > > +struct pru_irq_rsc { > > > + u8 type; > > > + u8 num_evts; > > > + struct pruss_int_map pru_intc_map[]; > > > +} __packed; > > > + > > > +#endif /* _PRU_RPROC_H_ */ > > > -- > > > 2.29.0 > > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel