Re: [kvm-unit-tests PATCH v7 09/13] arm/arm64: ITS: Commands

[Zenghui Yu <yuzenghui@huawei.com>]

Hi Eric,

On 2020/3/20 17:24, Eric Auger wrote:
> Implement main ITS commands. The code is largely inherited from
> the ITS driver.
> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>

[...]

> +/* ITS COMMANDS */
> +
> +static void its_encode_cmd(struct its_cmd_block *cmd, u8 cmd_nr)
> +{
> +	cmd->raw_cmd[0] &= ~0xffUL;
> +	cmd->raw_cmd[0] |= cmd_nr;
> +}
> +
> +static void its_encode_devid(struct its_cmd_block *cmd, u32 devid)
> +{
> +	cmd->raw_cmd[0] &= BIT_ULL(32) - 1;
> +	cmd->raw_cmd[0] |= ((u64)devid) << 32;
> +}
> +
> +static void its_encode_event_id(struct its_cmd_block *cmd, u32 id)
> +{
> +	cmd->raw_cmd[1] &= ~0xffffffffUL;
> +	cmd->raw_cmd[1] |= id;
> +}
> +
> +static void its_encode_phys_id(struct its_cmd_block *cmd, u32 phys_id)
> +{
> +	cmd->raw_cmd[1] &= 0xffffffffUL;
> +	cmd->raw_cmd[1] |= ((u64)phys_id) << 32;
> +}
> +
> +static void its_encode_size(struct its_cmd_block *cmd, u8 size)
> +{
> +	cmd->raw_cmd[1] &= ~0x1fUL;
> +	cmd->raw_cmd[1] |= size & 0x1f;
> +}
> +
> +static void its_encode_itt(struct its_cmd_block *cmd, u64 itt_addr)
> +{
> +	cmd->raw_cmd[2] &= ~0xffffffffffffUL;
> +	cmd->raw_cmd[2] |= itt_addr & 0xffffffffff00UL;
> +}
> +
> +static void its_encode_valid(struct its_cmd_block *cmd, int valid)
> +{
> +	cmd->raw_cmd[2] &= ~(1UL << 63);
> +	cmd->raw_cmd[2] |= ((u64)!!valid) << 63;
> +}
> +
> +static void its_encode_target(struct its_cmd_block *cmd, u64 target_addr)
> +{
> +	cmd->raw_cmd[2] &= ~(0xfffffffffUL << 16);
> +	cmd->raw_cmd[2] |= (target_addr & (0xffffffffUL << 16));
> +}
> +
> +static void its_encode_collection(struct its_cmd_block *cmd, u16 col)
> +{
> +	cmd->raw_cmd[2] &= ~0xffffUL;
> +	cmd->raw_cmd[2] |= col;
> +}

The command encoding can be refactored like:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4d36f136d57aea6f6440886106e246bb7e5918d8

which will look much clearer.

[...]

> +static void its_send_single_command(its_cmd_builder_t builder,
> +				    struct its_cmd_desc *desc)
> +{
> +	struct its_cmd_block *cmd, *next_cmd;
> +
> +	cmd = its_allocate_entry();
> +	builder(cmd, desc);
> +	next_cmd = its_post_commands();
> +
> +	its_wait_for_range_completion(cmd, next_cmd);
> +}
> +
> +

extra line.

> +static void its_build_mapd_cmd(struct its_cmd_block *cmd,
> +			       struct its_cmd_desc *desc)
> +{
> +	unsigned long itt_addr;
> +	u8 size = 12; /* 4096 eventids */

Maybe use desc->its_mapd_cmd.dev->nr_ites instead as we already have it?

> +
> +	itt_addr = (unsigned long)(virt_to_phys(desc->its_mapd_cmd.dev->itt));
> +	itt_addr = ALIGN(itt_addr, ITS_ITT_ALIGN);
> +
> +	its_encode_cmd(cmd, GITS_CMD_MAPD);
> +	its_encode_devid(cmd, desc->its_mapd_cmd.dev->device_id);
> +	its_encode_size(cmd, size - 1);
> +	its_encode_itt(cmd, itt_addr);
> +	its_encode_valid(cmd, desc->its_mapd_cmd.valid);
> +	its_fixup_cmd(cmd);
> +	if (desc->verbose)
> +		printf("ITS: MAPD devid=%d size = 0x%x itt=0x%lx valid=%d\n",
> +			desc->its_mapd_cmd.dev->device_id,
> +			size, itt_addr, desc->its_mapd_cmd.valid);
> +

extra line.

All of these are trivial things and feel free to ignore them,
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>


Thanks

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