linux/drivers/net/ipa/ipa.h
Alex Elder 3c6ccdde0f net: ipa: repurpose CLOCK_HELD flag
The previous patch causes a system resume to be triggered when a
packet is available for receipt on a suspended RX endpoint.

The CLOCK_HELD flag was previously used to indicate that an extra
clock reference was held, preventing suspend.  But we no longer need
such a flag:
  - We take an initial reference in ipa_config().
  - That reference is held until ipa_suspend() releases it.
  - A subsequent system resume leads to a reference getting
    re-acquired in ipa_resume().
  - This can repeat until ultimately the module is removed, where
    ipa_remove() releases the reference.
We no longer need a special flag to determine whether this extra
reference is held--it is, provided probe has completed successfully
and the driver is not suspended (or removed).

On the other hand, once suspended, it's possible for more than one
endpoint to trip the IPA SUSPEND interrupt, and we only want to
trigger the system resume once.  So repurpose the Boolean CLOCK_HELD
flag to record whether the IPA SUSPEND handler should initiate a
system resume.

The flag will be be cleared each time ipa_suspend() is called,
*before* any endpoints are suspended.  And it will be set inside the
IPA SUSPEND interrupt handler exactly once per suspend.

Rename the flag IPA_FLAG_RESUMED to reflect its new purpose.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-18 17:47:07 -07:00

169 lines
5.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
* Copyright (C) 2018-2020 Linaro Ltd.
*/
#ifndef _IPA_H_
#define _IPA_H_
#include <linux/types.h>
#include <linux/device.h>
#include <linux/notifier.h>
#include <linux/pm_wakeup.h>
#include "ipa_version.h"
#include "gsi.h"
#include "ipa_mem.h"
#include "ipa_qmi.h"
#include "ipa_endpoint.h"
#include "ipa_interrupt.h"
struct clk;
struct icc_path;
struct net_device;
struct platform_device;
struct ipa_clock;
struct ipa_smp2p;
struct ipa_interrupt;
/**
* enum ipa_flag - IPA state flags
* @IPA_FLAG_RESUMED: Whether resume from suspend has been signaled
* @IPA_FLAG_COUNT: Number of defined IPA flags
*/
enum ipa_flag {
IPA_FLAG_RESUMED,
IPA_FLAG_COUNT, /* Last; not a flag */
};
/**
* struct ipa - IPA information
* @gsi: Embedded GSI structure
* @flags: Boolean state flags
* @version: IPA hardware version
* @pdev: Platform device
* @modem_rproc: Remoteproc handle for modem subsystem
* @smp2p: SMP2P information
* @clock: IPA clocking information
* @table_addr: DMA address of filter/route table content
* @table_virt: Virtual address of filter/route table content
* @interrupt: IPA Interrupt information
* @uc_loaded: true after microcontroller has reported it's ready
* @reg_addr: DMA address used for IPA register access
* @reg_virt: Virtual address used for IPA register access
* @mem_addr: DMA address of IPA-local memory space
* @mem_virt: Virtual address of IPA-local memory space
* @mem_offset: Offset from @mem_virt used for access to IPA memory
* @mem_size: Total size (bytes) of memory at @mem_virt
* @mem: Array of IPA-local memory region descriptors
* @imem_iova: I/O virtual address of IPA region in IMEM
* @imem_size; Size of IMEM region
* @smem_iova: I/O virtual address of IPA region in SMEM
* @smem_size; Size of SMEM region
* @zero_addr: DMA address of preallocated zero-filled memory
* @zero_virt: Virtual address of preallocated zero-filled memory
* @zero_size: Size (bytes) of preallocated zero-filled memory
* @wakeup_source: Wakeup source information
* @available: Bit mask indicating endpoints hardware supports
* @filter_map: Bit mask indicating endpoints that support filtering
* @initialized: Bit mask indicating endpoints initialized
* @set_up: Bit mask indicating endpoints set up
* @enabled: Bit mask indicating endpoints enabled
* @endpoint: Array of endpoint information
* @channel_map: Mapping of GSI channel to IPA endpoint
* @name_map: Mapping of IPA endpoint name to IPA endpoint
* @setup_complete: Flag indicating whether setup stage has completed
* @modem_state: State of modem (stopped, running)
* @modem_netdev: Network device structure used for modem
* @qmi: QMI information
*/
struct ipa {
struct gsi gsi;
DECLARE_BITMAP(flags, IPA_FLAG_COUNT);
enum ipa_version version;
struct platform_device *pdev;
struct rproc *modem_rproc;
struct notifier_block nb;
void *notifier;
struct ipa_smp2p *smp2p;
struct ipa_clock *clock;
dma_addr_t table_addr;
__le64 *table_virt;
struct ipa_interrupt *interrupt;
bool uc_loaded;
dma_addr_t reg_addr;
void __iomem *reg_virt;
dma_addr_t mem_addr;
void *mem_virt;
u32 mem_offset;
u32 mem_size;
const struct ipa_mem *mem;
unsigned long imem_iova;
size_t imem_size;
unsigned long smem_iova;
size_t smem_size;
dma_addr_t zero_addr;
void *zero_virt;
size_t zero_size;
/* Bit masks indicating endpoint state */
u32 available; /* supported by hardware */
u32 filter_map;
u32 initialized;
u32 set_up;
u32 enabled;
struct ipa_endpoint endpoint[IPA_ENDPOINT_MAX];
struct ipa_endpoint *channel_map[GSI_CHANNEL_COUNT_MAX];
struct ipa_endpoint *name_map[IPA_ENDPOINT_COUNT];
bool setup_complete;
atomic_t modem_state; /* enum ipa_modem_state */
struct net_device *modem_netdev;
struct ipa_qmi qmi;
};
/**
* ipa_setup() - Perform IPA setup
* @ipa: IPA pointer
*
* IPA initialization is broken into stages: init; config; and setup.
* (These have inverses exit, deconfig, and teardown.)
*
* Activities performed at the init stage can be done without requiring
* any access to IPA hardware. Activities performed at the config stage
* require the IPA clock to be running, because they involve access
* to IPA registers. The setup stage is performed only after the GSI
* hardware is ready (more on this below). The setup stage allows
* the AP to perform more complex initialization by issuing "immediate
* commands" using a special interface to the IPA.
*
* This function, @ipa_setup(), starts the setup stage.
*
* In order for the GSI hardware to be functional it needs firmware to be
* loaded (in addition to some other low-level initialization). This early
* GSI initialization can be done either by Trust Zone on the AP or by the
* modem.
*
* If it's done by Trust Zone, the AP loads the GSI firmware and supplies
* it to Trust Zone to verify and install. When this completes, if
* verification was successful, the GSI layer is ready and ipa_setup()
* implements the setup phase of initialization.
*
* If the modem performs early GSI initialization, the AP needs to know
* when this has occurred. An SMP2P interrupt is used for this purpose,
* and receipt of that interrupt triggers the call to ipa_setup().
*/
int ipa_setup(struct ipa *ipa);
#endif /* _IPA_H_ */