On 2/4/19 9:19 AM, Andrew F. Davis wrote:
> On 2/4/19 8:22 AM, Roger Quadros wrote:
>> From: David Lechner <david@xxxxxxxxxxxxxx>
>>
>> This adds a special handler to the default remoteproc ELF firmware
>> loader that looks up the memory map on TI PRU firmware files.
>>
>> These processors have multiple memory maps that share the same address
>> space, so we need to know the page in addition to the physical address
>> in order to translate the address to a local CPU address.
>>
>> Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx>
>> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
>> ---
>> drivers/remoteproc/remoteproc_elf_loader.c | 117 +++++++++++++++++++++++++++--
>> include/uapi/linux/elf-em.h | 1 +
>> 2 files changed, 112 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/remoteproc/remoteproc_elf_loader.c b/drivers/remoteproc/remoteproc_elf_loader.c
>> index 8888d39..79c9d39 100644
>> --- a/drivers/remoteproc/remoteproc_elf_loader.c
>> +++ b/drivers/remoteproc/remoteproc_elf_loader.c
>> @@ -32,6 +32,103 @@
>>
>> #include "remoteproc_internal.h"
>>
>> +#define SHT_TI_PHATTRS 0x7F000004
>> +#define SHT_TI_SH_PAGE 0x7F000007
>> +
>> +struct elf32_ti_phattrs {
>> + Elf32_Half pha_seg_id; /* Segment id */
>> + Elf32_Half pha_tag_id; /* Attribute kind id */
>> + union {
>> + Elf32_Off pha_offset; /* byte offset within the section */
>> + Elf32_Word pha_value; /* Constant tag value */
>> + } pha_un;
>> +};
>> +
>> +/* this struct is reverse engineered, so not sure what most of the values are */
>
> Do we really not know? Someone should go check this, if they are not
> used then for now label them "unused", not "unknown".
I am following up internally within TI to get more concrete definitions
around this.
In anycase, on AM65x SoC, I actually had to implement a custom ELF
loading function due to the differences in hardware behavior [1], so I
think we should consider moving this whole logic into the PRU remoteproc
driver itself, and see if it is possible to keep the generic ELF loader
code clean and without having to introduce the flag parameter to
rproc_da_to_va() function.
regards
Suman
[1]
http://git.ti.com/gitweb/?p=ti-linux-kernel/ti-linux-kernel.git;a=commitdiff;h=529c7767b4f3cff0568c8867cb18b39526d07785
>
> Andrew
>
>> +struct ti_section_page {
>> + u32 unk0;
>> + u32 unk1;
>> + u32 unk2;
>> + u32 unk3;
>> + u32 unk4;
>> + u16 size;
>> + u16 unk5;
>> + u16 unk6;
>> + u8 data[0]; /* array of size */
>> +};
>> +
>> +/**
>> + * rproc_elf_segment_to_map() - Gets memory map for segment
>> + * @id: segment id
>> + * @elf_data: pointer to ELF file data
>> + *
>> + * Returns the memory map for the segment.
>> + */
>> +static int rproc_elf_segment_to_map(u32 id, const u8 *elf_data)
>> +{
>> + struct elf32_hdr *ehdr;
>> + struct elf32_shdr *shdr;
>> + struct elf32_ti_phattrs *ti_attrs = NULL;
>> + int i;
>> +
>> + ehdr = (struct elf32_hdr *)elf_data;
>> + shdr = (struct elf32_shdr *)(elf_data + ehdr->e_shoff);
>> +
>> + if (ehdr->e_machine != EM_TI_PRU)
>> + return 0;
>> +
>> + for (i = 0; i < ehdr->e_shnum; i++, shdr++) {
>> + if (shdr->sh_type == SHT_TI_PHATTRS) {
>> + ti_attrs = (struct elf32_ti_phattrs *)(elf_data + shdr->sh_offset);
>> + break;
>> + }
>> + }
>> +
>> + if (!ti_attrs)
>> + return 0;
>> +
>> + /* list is terminated by tag id == 0 (PHA_NULL) */
>> + for (; ti_attrs->pha_tag_id; ti_attrs++) {
>> + if (ti_attrs->pha_tag_id == 3 && ti_attrs->pha_seg_id == id)
>> + return ti_attrs->pha_un.pha_value;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +/**
>> + * rproc_elf_section_to_map() - Gets memory map for section
>> + * @id: segment id
>> + * @elf_data: pointer to ELF file data
>> + *
>> + * Returns the memory map for the section.
>> + */
>> +static int rproc_elf_section_to_map(u32 id, const u8 *elf_data)
>> +{
>> + struct elf32_hdr *ehdr;
>> + struct elf32_shdr *shdr;
>> + struct ti_section_page *map = NULL;
>> + int i;
>> +
>> + ehdr = (struct elf32_hdr *)elf_data;
>> + shdr = (struct elf32_shdr *)(elf_data + ehdr->e_shoff);
>> +
>> + if (ehdr->e_machine != EM_TI_PRU)
>> + return 0;
>> +
>> + for (i = 0; i < ehdr->e_shnum; i++, shdr++) {
>> + if (shdr->sh_type == SHT_TI_SH_PAGE) {
>> + map = (struct ti_section_page *)(elf_data + shdr->sh_offset);
>> + break;
>> + }
>> + }
>> +
>> + if (!map || id >= map->size)
>> + return 0;
>> +
>> + return map->data[id];
>> +}
>> +
>> /**
>> * rproc_elf_sanity_check() - Sanity Check ELF firmware image
>> * @rproc: the remote processor handle
>> @@ -147,7 +244,7 @@ int rproc_elf_load_segments(struct rproc *rproc, const struct firmware *fw)
>> struct device *dev = &rproc->dev;
>> struct elf32_hdr *ehdr;
>> struct elf32_phdr *phdr;
>> - int i, ret = 0;
>> + int i, map, ret = 0;
>> const u8 *elf_data = fw->data;
>>
>> ehdr = (struct elf32_hdr *)elf_data;
>> @@ -181,8 +278,10 @@ int rproc_elf_load_segments(struct rproc *rproc, const struct firmware *fw)
>> break;
>> }
>>
>> + map = rproc_elf_segment_to_map(i, elf_data);
>> +
>> /* grab the kernel address for this device address */
>> - ptr = rproc_da_to_va(rproc, da, memsz, 0);
>> + ptr = rproc_da_to_va(rproc, da, memsz, map);
>> if (!ptr) {
>> dev_err(dev, "bad phdr da 0x%x mem 0x%x\n", da, memsz);
>> ret = -EINVAL;
>> @@ -209,7 +308,7 @@ int rproc_elf_load_segments(struct rproc *rproc, const struct firmware *fw)
>> EXPORT_SYMBOL(rproc_elf_load_segments);
>>
>> static struct elf32_shdr *
>> -find_table(struct device *dev, struct elf32_hdr *ehdr, size_t fw_size)
>> +find_table(struct device *dev, struct elf32_hdr *ehdr, size_t fw_size, int *id)
>> {
>> struct elf32_shdr *shdr;
>> int i;
>> @@ -261,6 +360,9 @@ find_table(struct device *dev, struct elf32_hdr *ehdr, size_t fw_size)
>> return NULL;
>> }
>>
>> + if (id)
>> + *id = i;
>> +
>> return shdr;
>> }
>>
>> @@ -288,7 +390,7 @@ int rproc_elf_load_rsc_table(struct rproc *rproc, const struct firmware *fw)
>>
>> ehdr = (struct elf32_hdr *)elf_data;
>>
>> - shdr = find_table(dev, ehdr, fw->size);
>> + shdr = find_table(dev, ehdr, fw->size, NULL);
>> if (!shdr)
>> return -EINVAL;
>>
>> @@ -328,11 +430,14 @@ struct resource_table *rproc_elf_find_loaded_rsc_table(struct rproc *rproc,
>> {
>> struct elf32_hdr *ehdr = (struct elf32_hdr *)fw->data;
>> struct elf32_shdr *shdr;
>> + int id, map;
>>
>> - shdr = find_table(&rproc->dev, ehdr, fw->size);
>> + shdr = find_table(&rproc->dev, ehdr, fw->size, &id);
>> if (!shdr)
>> return NULL;
>>
>> - return rproc_da_to_va(rproc, shdr->sh_addr, shdr->sh_size, 0);
>> + map = rproc_elf_section_to_map(id, fw->data);
>> +
>> + return rproc_da_to_va(rproc, shdr->sh_addr, shdr->sh_size, map);
>> }
>> EXPORT_SYMBOL(rproc_elf_find_loaded_rsc_table);
>> diff --git a/include/uapi/linux/elf-em.h b/include/uapi/linux/elf-em.h
>> index 0c3000fa..70b487a 100644
>> --- a/include/uapi/linux/elf-em.h
>> +++ b/include/uapi/linux/elf-em.h
>> @@ -38,6 +38,7 @@
>> #define EM_BLACKFIN 106 /* ADI Blackfin Processor */
>> #define EM_ALTERA_NIOS2 113 /* Altera Nios II soft-core processor */
>> #define EM_TI_C6000 140 /* TI C6X DSPs */
>> +#define EM_TI_PRU 144 /* TI Programmable Realtime Unit */
>> #define EM_AARCH64 183 /* ARM 64 bit */
>> #define EM_TILEPRO 188 /* Tilera TILEPro */
>> #define EM_MICROBLAZE 189 /* Xilinx MicroBlaze */
>>
