Commit 64edfaa9 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

irqchip/gic-v4.1: Implement the v4.1 flavour of VMAPP 



The ITS VMAPP command gains some new fields with GICv4.1:
- a default doorbell, which allows a single doorbell to be used for
  all the VLPIs routed to a given VPE
- a pointer to the configuration table (instead of having it in a register
  that gets context switched)
- a flag indicating whether this is the first map or the last unmap for
  this particular VPE
- a flag indicating whether the pending table is known to be zeroed, or not

Plumb in the new fields in the VMAPP builder, and add the map/unmap
refcounting so that the ITS can do the right thing.

Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Reviewed-by: default avatarZenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-7-maz@kernel.org
parent 5e516846

drivers/irqchip/irq-gic-v3-its.c

+55 −5
Original line number Diff line number Diff line
@@ -449,6 +449,27 @@ static void its_encode_vpt_size(struct its_cmd_block *cmd, u8 vpt_size) 
	its_mask_encode(&cmd->raw_cmd[3], vpt_size, 4, 0);

}



static void its_encode_vconf_addr(struct its_cmd_block *cmd, u64 vconf_pa)

{

	its_mask_encode(&cmd->raw_cmd[0], vconf_pa >> 16, 51, 16);

}



static void its_encode_alloc(struct its_cmd_block *cmd, bool alloc)

{

	its_mask_encode(&cmd->raw_cmd[0], alloc, 8, 8);

}



static void its_encode_ptz(struct its_cmd_block *cmd, bool ptz)

{

	its_mask_encode(&cmd->raw_cmd[0], ptz, 9, 9);

}



static void its_encode_vmapp_default_db(struct its_cmd_block *cmd,

					u32 vpe_db_lpi)

{

	its_mask_encode(&cmd->raw_cmd[1], vpe_db_lpi, 31, 0);

}



static inline void its_fixup_cmd(struct its_cmd_block *cmd)

{

	/* Let's fixup BE commands */
@@ -632,19 +653,45 @@ static struct its_vpe *its_build_vmapp_cmd(struct its_node *its, 
					   struct its_cmd_block *cmd,

					   struct its_cmd_desc *desc)

{

	unsigned long vpt_addr;

	unsigned long vpt_addr, vconf_addr;

	u64 target;



	vpt_addr = virt_to_phys(page_address(desc->its_vmapp_cmd.vpe->vpt_page));

	target = desc->its_vmapp_cmd.col->target_address + its->vlpi_redist_offset;

	bool alloc;



	its_encode_cmd(cmd, GITS_CMD_VMAPP);

	its_encode_vpeid(cmd, desc->its_vmapp_cmd.vpe->vpe_id);

	its_encode_valid(cmd, desc->its_vmapp_cmd.valid);



	if (!desc->its_vmapp_cmd.valid) {

		if (is_v4_1(its)) {

			alloc = !atomic_dec_return(&desc->its_vmapp_cmd.vpe->vmapp_count);

			its_encode_alloc(cmd, alloc);

		}



		goto out;

	}



	vpt_addr = virt_to_phys(page_address(desc->its_vmapp_cmd.vpe->vpt_page));

	target = desc->its_vmapp_cmd.col->target_address + its->vlpi_redist_offset;



	its_encode_target(cmd, target);

	its_encode_vpt_addr(cmd, vpt_addr);

	its_encode_vpt_size(cmd, LPI_NRBITS - 1);



	if (!is_v4_1(its))

		goto out;



	vconf_addr = virt_to_phys(page_address(desc->its_vmapp_cmd.vpe->its_vm->vprop_page));



	alloc = !atomic_fetch_inc(&desc->its_vmapp_cmd.vpe->vmapp_count);



	its_encode_alloc(cmd, alloc);



	/* We can only signal PTZ when alloc==1. Why do we have two bits? */

	its_encode_ptz(cmd, alloc);

	its_encode_vconf_addr(cmd, vconf_addr);

	its_encode_vmapp_default_db(cmd, desc->its_vmapp_cmd.vpe->vpe_db_lpi);



out:

	its_fixup_cmd(cmd);



	return valid_vpe(its, desc->its_vmapp_cmd.vpe);
@@ -3492,6 +3539,9 @@ static int its_vpe_init(struct its_vpe *vpe) 


	vpe->vpe_id = vpe_id;

	vpe->vpt_page = vpt_page;

	if (gic_rdists->has_rvpeid)

		atomic_set(&vpe->vmapp_count, 0);

	else

		vpe->vpe_proxy_event = -1;



	return 0;

include/linux/irqchip/arm-gic-v4.h

+14 −4
Original line number Diff line number Diff line
@@ -39,8 +39,20 @@ struct its_vpe { 
	irq_hw_number_t		vpe_db_lpi;

	/* VPE resident */

	bool			resident;

	union {

		/* GICv4.0 implementations */

		struct {

			/* VPE proxy mapping */

			int	vpe_proxy_event;

			/* Implementation Defined Area Invalid */

			bool	idai;

		};

		/* GICv4.1 implementations */

		struct {

			atomic_t vmapp_count;

		};

	};



	/*

	 * This collection ID is used to indirect the target

	 * redistributor for this VPE. The ID itself isn't involved in
@@ -49,8 +61,6 @@ struct its_vpe { 
	u16			col_idx;

	/* Unique (system-wide) VPE identifier */

	u16			vpe_id;

	/* Implementation Defined Area Invalid */

	bool			idai;

	/* Pending VLPIs on schedule out? */

	bool			pending_last;

};

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