On 5/21/24 12:56 PM, Mathieu Poirier wrote:
> Hi Tanmay,
>
> On Fri, May 10, 2024 at 05:51:25PM -0700, Tanmay Shah wrote:
>> It is possible that remote processor is already running before
>> linux boot or remoteproc platform driver probe. Implement required
>> remoteproc framework ops to provide resource table address and
>> connect or disconnect with remote processor in such case.
>>
>> Signed-off-by: Tanmay Shah <tanmay.s...@amd.com>
>> ---
>>
>> Changes in v2:
>> - Fix following sparse warnings
>>
>> drivers/remoteproc/xlnx_r5_remoteproc.c:827:21: sparse: expected struct
>> rsc_tbl_data *rsc_data_va
>> drivers/remoteproc/xlnx_r5_remoteproc.c:844:18: sparse: expected struct
>> resource_table *rsc_addr
>> drivers/remoteproc/xlnx_r5_remoteproc.c:898:24: sparse: expected void
>> volatile [noderef] __iomem *addr
>>
>> drivers/remoteproc/xlnx_r5_remoteproc.c | 164 +++++++++++++++++++++++-
>> 1 file changed, 160 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/remoteproc/xlnx_r5_remoteproc.c
>> b/drivers/remoteproc/xlnx_r5_remoteproc.c
>> index 84243d1dff9f..039370cffa32 100644
>> --- a/drivers/remoteproc/xlnx_r5_remoteproc.c
>> +++ b/drivers/remoteproc/xlnx_r5_remoteproc.c
>> @@ -25,6 +25,10 @@
>> /* RX mailbox client buffer max length */
>> #define MBOX_CLIENT_BUF_MAX (IPI_BUF_LEN_MAX + \
>> sizeof(struct zynqmp_ipi_message))
>> +
>> +#define RSC_TBL_XLNX_MAGIC ((uint32_t)'x' << 24 | (uint32_t)'a' << 16 | \
>> + (uint32_t)'m' << 8 | (uint32_t)'p')
>> +
>> /*
>> * settings for RPU cluster mode which
>> * reflects possible values of xlnx,cluster-mode dt-property
>> @@ -73,6 +77,15 @@ struct mbox_info {
>> struct mbox_chan *rx_chan;
>> };
>>
>> +/* Xilinx Platform specific data structure */
>> +struct rsc_tbl_data {
>> + const int version;
>> + const u32 magic_num;
>> + const u32 comp_magic_num;
>
> Why is a complement magic number needed?
Actually magic number is 64-bit. There is good chance that
firmware can have 32-bit op-code or data same as magic number, but very less
chance of its complement in the next address. So, we can assume magic number
is 64-bit.
>
>> + const u32 rsc_tbl_size;
>> + const uintptr_t rsc_tbl;
>> +} __packed;
>> +
>> /*
>> * Hardcoded TCM bank values. This will stay in driver to maintain backward
>> * compatibility with device-tree that does not have TCM information.
>> @@ -95,20 +108,24 @@ static const struct mem_bank_data
>> zynqmp_tcm_banks_lockstep[] = {
>> /**
>> * struct zynqmp_r5_core
>> *
>> + * @rsc_tbl_va: resource table virtual address
>> * @dev: device of RPU instance
>> * @np: device node of RPU instance
>> * @tcm_bank_count: number TCM banks accessible to this RPU
>> * @tcm_banks: array of each TCM bank data
>> * @rproc: rproc handle
>> + * @rsc_tbl_size: resource table size retrieved from remote
>> * @pm_domain_id: RPU CPU power domain id
>> * @ipi: pointer to mailbox information
>> */
>> struct zynqmp_r5_core {
>> + struct resource_table *rsc_tbl_va;
>
> Shouldn't this be of type "void __iomem *"? Did sparse give you trouble on
> that
> one?
I fixed sparse warnings with typecast below [1].
>
>> struct device *dev;
>> struct device_node *np;
>> int tcm_bank_count;
>> struct mem_bank_data **tcm_banks;
>> struct rproc *rproc;
>> + u32 rsc_tbl_size;
>> u32 pm_domain_id;
>> struct mbox_info *ipi;
>> };
>> @@ -621,10 +638,19 @@ static int zynqmp_r5_rproc_prepare(struct rproc *rproc)
>> {
>> int ret;
>>
>> - ret = add_tcm_banks(rproc);
>> - if (ret) {
>> - dev_err(&rproc->dev, "failed to get TCM banks, err %d\n", ret);
>> - return ret;
>> + /**
>
> Using "/**" is for comments that will endup in the documentation, which I
> don't
> think is needed here. Please correct throughout the patch.
Thanks. Ack, I will use only /* format.
>
>> + * For attach/detach use case, Firmware is already loaded so
>> + * TCM isn't really needed at all. Also, for security TCM can be
>> + * locked in such case and linux may not have access at all.
>> + * So avoid adding TCM banks. TCM power-domains requested during attach
>> + * callback.
>> + */
>> + if (rproc->state != RPROC_DETACHED) {
>> + ret = add_tcm_banks(rproc);
>> + if (ret) {
>> + dev_err(&rproc->dev, "failed to get TCM banks, err
>> %d\n", ret);
>> + return ret;
>> + }
>> }
>>
>> ret = add_mem_regions_carveout(rproc);
>> @@ -662,6 +688,123 @@ static int zynqmp_r5_rproc_unprepare(struct rproc
>> *rproc)
>> return 0;
>> }
>>
>> +static struct resource_table *zynqmp_r5_get_loaded_rsc_table(struct rproc
>> *rproc,
>> + size_t *size)
>> +{
>> + struct zynqmp_r5_core *r5_core;
>> +
>> + r5_core = rproc->priv;
>> +
>> + *size = r5_core->rsc_tbl_size;
>> +
>> + return r5_core->rsc_tbl_va;
>> +}
>> +
>> +static int zynqmp_r5_get_rsc_table_va(struct zynqmp_r5_core *r5_core)
>> +{
>> + struct device *dev = r5_core->dev;
>> + struct rsc_tbl_data *rsc_data_va;
>> + struct resource_table *rsc_addr;
>> + struct resource res_mem;
>> + struct device_node *np;
>> + int ret;
>> +
>> + /**
>> + * It is expected from remote processor firmware to provide resource
>> + * table address via struct rsc_tbl_data data structure.
>> + * Start address of first entry under "memory-region" property list
>> + * contains that data structure which holds resource table address, size
>> + * and some magic number to validate correct resource table entry.
>> + */
>> + np = of_parse_phandle(r5_core->np, "memory-region", 0);
>> + if (!np) {
>> + dev_err(dev, "failed to get memory region dev node\n");
>> + return -EINVAL;
>> + }
>> +
>> + ret = of_address_to_resource(np, 0, &res_mem);
>> + if (ret) {
>> + dev_err(dev, "failed to get memory-region resource addr\n");
>> + return -EINVAL;
>> + }
>> +
>> + rsc_data_va = (struct rsc_tbl_data *)devm_ioremap_wc(dev, res_mem.start,
>> + sizeof(struct
>> rsc_tbl_data));
>
> There is no point in holding memory until the driver is unloaded. Please use
> ioremap_wc() and free at the end of the function.
>
Ack.
>> + if (!rsc_data_va) {
>> + dev_err(dev, "failed to map resource table data address\n");
>> + return -EIO;
>> + }
>> +
>> + /**
>> + * If RSC_TBL_XLNX_MAGIC number and its complement isn't found then
>> + * do not consider resource table address valid and don't attach
>> + */
>> + if (rsc_data_va->magic_num != RSC_TBL_XLNX_MAGIC ||
>> + rsc_data_va->comp_magic_num != ~RSC_TBL_XLNX_MAGIC) {
>> + dev_dbg(dev, "invalid magic number, won't attach\n");
>> + return -EINVAL;
>> + }
>> +
>> + rsc_addr = (struct resource_table *)ioremap_wc(rsc_data_va->rsc_tbl,
>> +
>> rsc_data_va->rsc_tbl_size);
[1] Here typecast is done.
>> + if (!rsc_addr) {
>> + dev_err(dev, "failed to get rsc_addr\n");
>> + return -EINVAL;
>> + }
>> +
>> + /**
>> + * As of now resource table version 1 is expected. Don't fail to attach
>> + * but warn users about it.
>> + */
>> + if (rsc_addr->ver != 1)
>> + dev_warn(dev, "unexpected resource table version %d\n",
>> + rsc_addr->ver);
>> +
>> + r5_core->rsc_tbl_size = rsc_data_va->rsc_tbl_size;
>> + r5_core->rsc_tbl_va = rsc_addr;
>> +
>> + return 0;
>> +}
>> +
>> +static int zynqmp_r5_attach(struct rproc *rproc)
>> +{
>> + struct zynqmp_r5_core *r5_core = rproc->priv;
>> + int i, pm_domain_id, ret;
>> +
>> + /*
>> + * Firmware is loaded in TCM. Request TCM power domains to notify
>> + * platform management controller that TCM is in use. This will be
>> + * released during unprepare callback.
>> + */
>> + for (i = 0; i < r5_core->tcm_bank_count; i++) {
>> + pm_domain_id = r5_core->tcm_banks[i]->pm_domain_id;
>> + ret = zynqmp_pm_request_node(pm_domain_id,
>> + ZYNQMP_PM_CAPABILITY_ACCESS, 0,
>> + ZYNQMP_PM_REQUEST_ACK_BLOCKING);
>> + if (ret < 0)
>> + pr_warn("TCM %d can't be requested\n", i);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int zynqmp_r5_detach(struct rproc *rproc)
>> +{
>> + struct zynqmp_r5_core *r5_core = rproc->priv;
>> +
>> + /*
>> + * Generate last notification to remote after clearing virtio flag.
>> + * Remote can avoid polling on virtio reset flag if kick is generated
>> + * during detach by host and check virtio reset flag on kick interrupt.
>> + */
>> + zynqmp_r5_rproc_kick(rproc, 0);
>> +
>> + iounmap((void __iomem *)r5_core->rsc_tbl_va);
>> + r5_core->rsc_tbl_va = NULL;
>
> This is puzzling... What happens to ->tsc_tbl_va when the remote processor is
> re-attached?
Actually I don't see re-attach in life cycle. I might be missing something.
Following is lifecycle I have tested:
1) During driver probe, if resource table is found in memory, then state is
moved to detach.
2) Then user executes echo start > remoteproc* command, and state moved to
attach.
3) After work is done with remote, user executes echo stop > remoteproc*
command,
and state is moved to offline.
>From here, remote is offline state, and I can't re-attach to it without loading
firmware again. which is regular start/stop states. Please let me know if I am
missing
something.
>From here, load firmware, and executing echo start > remoteproc* moves
rproc state to running. Load firmware loads resource table from elf.
So, I believe attach is happening only during probe. And then, once r5 stops,
user
needs to load firmware and start R5. I think this use case is good for now.
>
> I will not look at the SRAM part. Please re-submit when we are done with the
> attach/detach feature.
>
Okay sounds good to me.
Reviews are still welcomed if anyone in the community decides to review it.
Thanks,
Tanmay
> Thanks,
> Mathieu
>
>> +
>> + return 0;
>> +}
>> +
>> static const struct rproc_ops zynqmp_r5_rproc_ops = {
>> .prepare = zynqmp_r5_rproc_prepare,
>> .unprepare = zynqmp_r5_rproc_unprepare,
>> @@ -673,6 +816,9 @@ static const struct rproc_ops zynqmp_r5_rproc_ops = {
>> .sanity_check = rproc_elf_sanity_check,
>> .get_boot_addr = rproc_elf_get_boot_addr,
>> .kick = zynqmp_r5_rproc_kick,
>> + .get_loaded_rsc_table = zynqmp_r5_get_loaded_rsc_table,
>> + .attach = zynqmp_r5_attach,
>> + .detach = zynqmp_r5_detach,
>> };
>>
>> /**
>> @@ -723,6 +869,16 @@ static struct zynqmp_r5_core
>> *zynqmp_r5_add_rproc_core(struct device *cdev)
>> goto free_rproc;
>> }
>>
>> + /*
>> + * Move rproc state to DETACHED to give one time opportunity to attach
>> + * if firmware is already available in the memory. This can happen if
>> + * firmware is loaded via debugger or by any other agent in the system.
>> + * If firmware isn't available in the memory and resource table isn't
>> found,
>> + * then rproc state stay OFFLINE.
>> + */
>> + if (!zynqmp_r5_get_rsc_table_va(r5_core))
>> + r5_rproc->state = RPROC_DETACHED;
>> +
>> r5_core->rproc = r5_rproc;
>> return r5_core;
>>
>> --
>> 2.25.1
>>
