Re: [PATCH v1 2/2] i3c: master: Add Nuvoton npcm845 i3c master driver

Stanley Chu
2024-08-05T06:27:23Z

On Thu, Aug 1, 2024 at 11:02 PM Krzysztof Kozlowski <krzk@kernel.org> wrote:
>
> On 01/08/2024 09:19, Stanley Chu wrote:
> > Add support for the Nuvoton npcm845 i3c controller which
> > implements I3C master functionality as defined in the MIPI
> > Alliance Specification for I3C, Version 1.0.
> >
> > The master role is supported in SDR mode only. IBI and Hot-join
> > requsts are supported.
> >
> > Signed-off-by: Stanley Chu <yschu@nuvoton.com>
> > Signed-off-by: James Chiang <cpchiang1@nuvoton.com>
> > ---
> > MAINTAINERS | 7 +
> > drivers/i3c/master/Kconfig | 14 +
> > drivers/i3c/master/Makefile | 1 +
> > drivers/i3c/master/npcm845-i3c-master.c | 2364 +++++++++++++++++++++++
> > 4 files changed, 2386 insertions(+)
> > create mode 100644 drivers/i3c/master/npcm845-i3c-master.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 42decde38320..2d30b6e418d8 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -2670,6 +2670,13 @@ F: Documentation/userspace-api/media/drivers/npcm-video.rst
> > F: drivers/media/platform/nuvoton/
> > F: include/uapi/linux/npcm-video.h
> >
> > +ARM/NUVOTON NPCM845 I3C MASTER DRIVER
>
> Use proper terminology. Master is gone since 2021, right?
>
> This applies everywhere.
>

Thanks for the review.
I will fix it in v2.

> > +M: Stanley Chu <yschu@nuvoton.com>
> > +M: James Chiang <cpchiang1@nuvoton.com>
> > +S: Maintained
> > +F: Documentation/devicetree/bindings/i3c/nuvoton,i3c-master.yaml
> > +F: drivers/i3c/master/npcm845-i3c-master.c
> > +
> > ARM/NUVOTON WPCM450 ARCHITECTURE
> > M: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
> > L: openbmc@lists.ozlabs.org (moderated for non-subscribers)
> > diff --git a/drivers/i3c/master/Kconfig b/drivers/i3c/master/Kconfig
> > index 90dee3ec5520..a71d504d4744 100644
> > --- a/drivers/i3c/master/Kconfig
> > +++ b/drivers/i3c/master/Kconfig
> > @@ -44,6 +44,20 @@ config SVC_I3C_MASTER
> > help
> > Support for Silvaco I3C Dual-Role Master Controller.
> >
> > +config NPCM845_I3C_MASTER
> > + tristate "Nuvoton NPCM845 I3C master driver"
> > + depends on I3C
> > + depends on HAS_IOMEM
> > + depends on ARCH_NPCM || COMPILE_TEST
> > + help
> > + Support for Nuvoton NPCM845 I3C Master Controller.
> > +
> > + This hardware is an instance of the SVC I3C controller; this
> > + driver adds platform specific support for NPCM845 hardware.
> > +
> > + This driver can also be built as a module. If so, the module
> > + will be called npcm845-i3c-master.
> > +
> > config MIPI_I3C_HCI
> > tristate "MIPI I3C Host Controller Interface driver (EXPERIMENTAL)"
> > depends on I3C
> > diff --git a/drivers/i3c/master/Makefile b/drivers/i3c/master/Makefile
> > index 3e97960160bc..3ed55113190a 100644
> > --- a/drivers/i3c/master/Makefile
> > +++ b/drivers/i3c/master/Makefile
> > @@ -3,4 +3,5 @@ obj-$(CONFIG_CDNS_I3C_MASTER) += i3c-master-cdns.o
> > obj-$(CONFIG_DW_I3C_MASTER) += dw-i3c-master.o
> > obj-$(CONFIG_AST2600_I3C_MASTER) += ast2600-i3c-master.o
> > obj-$(CONFIG_SVC_I3C_MASTER) += svc-i3c-master.o
> > +obj-$(CONFIG_NPCM845_I3C_MASTER) += npcm845-i3c-master.o
> > obj-$(CONFIG_MIPI_I3C_HCI) += mipi-i3c-hci/
> > diff --git a/drivers/i3c/master/npcm845-i3c-master.c b/drivers/i3c/master/npcm845-i3c-master.c
> > new file mode 100644
> > index 000000000000..19672fdbe2b8
> > --- /dev/null
> > +++ b/drivers/i3c/master/npcm845-i3c-master.c
> > @@ -0,0 +1,2364 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Nuvoton NPCM845 I3C master driver
> > + *
> > + * Copyright (C) 2024 Nuvoton Technology Corp.
> > + * Based on the work from svc i3c master driver and add platform
> > + * specific support for the NPCM845 hardware.
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/clk.h>
> > +#include <linux/completion.h>
> > +#include <linux/debugfs.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/errno.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/iopoll.h>
> > +#include <linux/list.h>
> > +#include <linux/module.h>
> > +#include <linux/mutex.h>
> > +#include <linux/of.h>
> > +#include <linux/reset.h>
> > +#include <linux/i3c/master.h>
> > +#include <linux/pinctrl/consumer.h>
> > +#include <linux/platform_device.h>
> > +
> > +/* Master Mode Registers */
> > +#define NPCM_I3C_MCONFIG 0x000
> > +#define NPCM_I3C_MCONFIG_MASTER_EN BIT(0)
> > +#define NPCM_I3C_MCONFIG_DISTO(x) FIELD_PREP(BIT(3), (x))
> > +#define NPCM_I3C_MCONFIG_HKEEP(x) FIELD_PREP(GENMASK(5, 4), (x))
> > +#define NPCM_I3C_MCONFIG_ODSTOP(x) FIELD_PREP(BIT(6), (x))
> > +#define NPCM_I3C_MCONFIG_PPBAUD(x) FIELD_PREP(GENMASK(11, 8), (x))
> > +#define NPCM_I3C_MCONFIG_PPLOW(x) FIELD_PREP(GENMASK(15, 12), (x))
> > +#define NPCM_I3C_MCONFIG_ODBAUD(x) FIELD_PREP(GENMASK(23, 16), (x))
> > +#define NPCM_I3C_MCONFIG_ODHPP(x) FIELD_PREP(BIT(24), (x))
> > +#define NPCM_I3C_MCONFIG_SKEW(x) FIELD_PREP(GENMASK(27, 25), (x))
> > +#define NPCM_I3C_MCONFIG_SKEW_MASK GENMASK(27, 25)
> > +#define NPCM_I3C_MCONFIG_I2CBAUD(x) FIELD_PREP(GENMASK(31, 28), (x))
> > +
> > +#define NPCM_I3C_MCTRL 0x084
> > +#define NPCM_I3C_MCTRL_REQUEST_MASK GENMASK(2, 0)
> > +#define NPCM_I3C_MCTRL_REQUEST(x) FIELD_GET(GENMASK(2, 0), (x))
> > +#define NPCM_I3C_MCTRL_REQUEST_NONE 0
> > +#define NPCM_I3C_MCTRL_REQUEST_START_ADDR 1
> > +#define NPCM_I3C_MCTRL_REQUEST_STOP 2
> > +#define NPCM_I3C_MCTRL_REQUEST_IBI_ACKNACK 3
> > +#define NPCM_I3C_MCTRL_REQUEST_PROC_DAA 4
> > +#define NPCM_I3C_MCTRL_REQUEST_FORCE_EXIT 6
> > +#define NPCM_I3C_MCTRL_REQUEST_AUTO_IBI 7
> > +#define NPCM_I3C_MCTRL_TYPE_I3C 0
> > +#define NPCM_I3C_MCTRL_TYPE_I2C BIT(4)
> > +#define NPCM_I3C_MCTRL_IBIRESP_AUTO 0
> > +#define NPCM_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE 0
> > +#define NPCM_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE BIT(7)
> > +#define NPCM_I3C_MCTRL_IBIRESP_NACK BIT(6)
> > +#define NPCM_I3C_MCTRL_IBIRESP_MANUAL GENMASK(7, 6)
> > +#define NPCM_I3C_MCTRL_DIR(x) FIELD_PREP(BIT(8), (x))
> > +#define NPCM_I3C_MCTRL_DIR_WRITE 0
> > +#define NPCM_I3C_MCTRL_DIR_READ 1
> > +#define NPCM_I3C_MCTRL_ADDR(x) FIELD_PREP(GENMASK(15, 9), (x))
> > +#define NPCM_I3C_MCTRL_RDTERM(x) FIELD_PREP(GENMASK(23, 16), (x))
> > +
> > +#define NPCM_I3C_MSTATUS 0x088
> > +#define NPCM_I3C_MSTATUS_STATE(x) FIELD_GET(GENMASK(2, 0), (x))
> > +#define NPCM_I3C_MSTATUS_STATE_DAA(x) (NPCM_I3C_MSTATUS_STATE(x) == 5)
> > +#define NPCM_I3C_MSTATUS_STATE_IDLE(x) (NPCM_I3C_MSTATUS_STATE(x) == 0)
> > +#define NPCM_I3C_MSTATUS_STATE_SLVREQ(x) (NPCM_I3C_MSTATUS_STATE(x) == 1)
> > +#define NPCM_I3C_MSTATUS_STATE_IBIACK(x) (NPCM_I3C_MSTATUS_STATE(x) == 6)
> > +#define NPCM_I3C_MSTATUS_BETWEEN(x) FIELD_GET(BIT(4), (x))
> > +#define NPCM_I3C_MSTATUS_NACKED(x) FIELD_GET(BIT(5), (x))
> > +#define NPCM_I3C_MSTATUS_IBITYPE(x) FIELD_GET(GENMASK(7, 6), (x))
> > +#define NPCM_I3C_MSTATUS_IBITYPE_IBI 1
> > +#define NPCM_I3C_MSTATUS_IBITYPE_MASTER_REQUEST 2
> > +#define NPCM_I3C_MSTATUS_IBITYPE_HOT_JOIN 3
> > +#define NPCM_I3C_MINT_SLVSTART BIT(8)
> > +#define NPCM_I3C_MINT_MCTRLDONE BIT(9)
> > +#define NPCM_I3C_MINT_COMPLETE BIT(10)
> > +#define NPCM_I3C_MINT_RXPEND BIT(11)
> > +#define NPCM_I3C_MINT_TXNOTFULL BIT(12)
> > +#define NPCM_I3C_MINT_IBIWON BIT(13)
> > +#define NPCM_I3C_MINT_ERRWARN BIT(15)
> > +#define NPCM_I3C_MSTATUS_SLVSTART(x) FIELD_GET(NPCM_I3C_MINT_SLVSTART, (x))
> > +#define NPCM_I3C_MSTATUS_MCTRLDONE(x) FIELD_GET(NPCM_I3C_MINT_MCTRLDONE, (x))
> > +#define NPCM_I3C_MSTATUS_COMPLETE(x) FIELD_GET(NPCM_I3C_MINT_COMPLETE, (x))
> > +#define NPCM_I3C_MSTATUS_RXPEND(x) FIELD_GET(NPCM_I3C_MINT_RXPEND, (x))
> > +#define NPCM_I3C_MSTATUS_TXNOTFULL(x) FIELD_GET(NPCM_I3C_MINT_TXNOTFULL, (x))
> > +#define NPCM_I3C_MSTATUS_IBIWON(x) FIELD_GET(NPCM_I3C_MINT_IBIWON, (x))
> > +#define NPCM_I3C_MSTATUS_ERRWARN(x) FIELD_GET(NPCM_I3C_MINT_ERRWARN, (x))
> > +#define NPCM_I3C_MSTATUS_IBIADDR(x) FIELD_GET(GENMASK(30, 24), (x))
> > +
> > +#define NPCM_I3C_IBIRULES 0x08C
> > +#define NPCM_I3C_IBIRULES_ADDR(slot, addr) FIELD_PREP(GENMASK(29, 0), \
> > + ((addr) & 0x3F) << ((slot) * 6))
> > +#define NPCM_I3C_IBIRULES_ADDRS 5
> > +#define NPCM_I3C_IBIRULES_MSB0 BIT(30)
> > +#define NPCM_I3C_IBIRULES_NOBYTE BIT(31)
> > +#define NPCM_I3C_IBIRULES_MANDBYTE 0
> > +#define NPCM_I3C_MINTSET 0x090
> > +#define NPCM_I3C_MINTCLR 0x094
> > +#define NPCM_I3C_MINTMASKED 0x098
> > +#define NPCM_I3C_MERRWARN 0x09C
> > +#define NPCM_I3C_MERRWARN_NACK(x) FIELD_GET(BIT(2), (x))
> > +#define NPCM_I3C_MERRWARN_TIMEOUT BIT(20)
> > +#define NPCM_I3C_MERRWARN_HCRC(x) FIELD_GET(BIT(10), (x))
> > +#define NPCM_I3C_MDMACTRL 0x0A0
> > +#define NPCM_I3C_MDMACTRL_DMAFB(x) FIELD_PREP(GENMASK(1, 0), (x))
> > +#define NPCM_I3C_MDMACTRL_DMATB(x) FIELD_PREP(GENMASK(3, 2), (x))
> > +#define NPCM_I3C_MDMACTRL_DMAWIDTH(x) FIELD_PREP(GENMASK(5, 4), (x))
> > +#define NPCM_I3C_MDATACTRL 0x0AC
> > +#define NPCM_I3C_MDATACTRL_FLUSHTB BIT(0)
> > +#define NPCM_I3C_MDATACTRL_FLUSHRB BIT(1)
> > +#define NPCM_I3C_MDATACTRL_UNLOCK_TRIG BIT(3)
> > +#define NPCM_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL GENMASK(5, 4)
> > +#define NPCM_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY 0
> > +#define NPCM_I3C_MDATACTRL_RXCOUNT(x) FIELD_GET(GENMASK(28, 24), (x))
> > +#define NPCM_I3C_MDATACTRL_TXCOUNT(x) FIELD_GET(GENMASK(20, 16), (x))
> > +#define NPCM_I3C_MDATACTRL_TXFULL BIT(30)
> > +#define NPCM_I3C_MDATACTRL_RXEMPTY BIT(31)
> > +
> > +#define NPCM_I3C_MWDATAB 0x0B0
> > +#define NPCM_I3C_MWDATAB_END BIT(8)
> > +
> > +#define NPCM_I3C_MWDATABE 0x0B4
> > +#define NPCM_I3C_MWDATAH 0x0B8
> > +#define NPCM_I3C_MWDATAHE 0x0BC
> > +#define NPCM_I3C_MRDATAB 0x0C0
> > +#define NPCM_I3C_MRDATAH 0x0C8
> > +
> > +#define NPCM_I3C_MDYNADDR 0x0E4
> > +#define NPCM_MDYNADDR_VALID BIT(0)
> > +#define NPCM_MDYNADDR_ADDR(x) FIELD_PREP(GENMASK(7, 1), (x))
> > +
> > +#define NPCM_I3C_PARTNO 0x06C
> > +#define NPCM_I3C_VENDORID 0x074
> > +#define NPCM_I3C_VENDORID_VID(x) FIELD_GET(GENMASK(14, 0), (x))
> > +
> > +#define NPCM_I3C_MAX_DEVS 32
> > +#define NPCM_I3C_PM_TIMEOUT_MS 1000
> > +
> > +/* This parameter depends on the implementation and may be tuned */
> > +#define NPCM_I3C_FIFO_SIZE 16
> > +#define NPCM_I3C_MAX_IBI_PAYLOAD_SIZE 8
> > +#define NPCM_I3C_MAX_RDTERM 255
> > +#define NPCM_I3C_MAX_PPBAUD 15
> > +#define NPCM_I3C_MAX_PPLOW 15
> > +#define NPCM_I3C_MAX_ODBAUD 255
> > +#define NPCM_I3C_MAX_I2CBAUD 15
> > +#define I3C_SCL_PP_PERIOD_NS_MIN 40
> > +#define I3C_SCL_OD_LOW_PERIOD_NS_MIN 200
> > +
> > +/* DMA definitions */
> > +#define MAX_DMA_COUNT 1024
> > +#define DMA_CH_TX 0
> > +#define DMA_CH_RX 1
> > +#define NPCM_GDMA_CTL(n) (n * 0x20 + 0x00)
> > +#define NPCM_GDMA_CTL_GDMAMS(x) FIELD_PREP(GENMASK(3, 2), (x))
> > +#define NPCM_GDMA_CTL_TWS(x) FIELD_PREP(GENMASK(13, 12), (x))
> > +#define NPCM_GDMA_CTL_GDMAEN BIT(0)
> > +#define NPCM_GDMA_CTL_DAFIX BIT(6)
> > +#define NPCM_GDMA_CTL_SAFIX BIT(7)
> > +#define NPCM_GDMA_CTL_SIEN BIT(8)
> > +#define NPCM_GDMA_CTL_DM BIT(15)
> > +#define NPCM_GDMA_CTL_TC BIT(18)
> > +#define NPCM_GDMA_SRCB(n) (n * 0x20 + 0x04)
> > +#define NPCM_GDMA_DSTB(n) (n * 0x20 + 0x08)
> > +#define NPCM_GDMA_TCNT(n) (n * 0x20 + 0x0C)
> > +#define NPCM_GDMA_CSRC(n) (n * 0x20 + 0x10)
> > +#define NPCM_GDMA_CDST(n) (n * 0x20 + 0x14)
> > +#define NPCM_GDMA_CTCNT(n) (n * 0x20 + 0x18)
> > +#define NPCM_GDMA_MUX(n) (((n & 0xFFFF) >> 12) * 2 + 6)
> > +#define GDMA_CH0_EN GENMASK(6, 5)
> > +#define GDMA_CH1_EN GENMASK(22, 21)
> > +
> > +struct npcm_i3c_cmd {
> > + u8 addr;
> > + bool rnw;
> > + u8 *in;
> > + const void *out;
> > + unsigned int len;
> > + unsigned int read_len;
> > + bool continued;
> > + bool use_dma;
> > +};
> > +
> > +struct npcm_i3c_xfer {
> > + struct list_head node;
> > + struct completion comp;
> > + int ret;
> > + unsigned int type;
> > + unsigned int ncmds;
> > + struct npcm_i3c_cmd cmds[];
> > +};
> > +
> > +struct npcm_i3c_regs_save {
> > + u32 mconfig;
> > + u32 mdynaddr;
> > +};
> > +
> > +struct npcm_dma_xfer_desc {
> > + const u8 *out;
> > + u8 *in;
> > + u32 len;
> > + bool rnw;
> > + bool end;
> > +};
> > +/**
> > + * struct npcm_i3c_master - npcm845 I3C Master structure
> > + * @base: I3C master controller
> > + * @dev: Corresponding device
> > + * @regs: Memory mapping
> > + * @saved_regs: Volatile values for PM operations
> > + * @free_slots: Bit array of available slots
> > + * @addrs: Array containing the dynamic addresses of each attached device
> > + * @descs: Array of descriptors, one per attached device
> > + * @hj_work: Hot-join work
> > + * @irq: Main interrupt
> > + * @pclk: System clock
> > + * @fclk: Fast clock (bus)
> > + * @sclk: Slow clock (other events)
> > + * @xferqueue: Transfer queue structure
> > + * @xferqueue.list: List member
> > + * @xferqueue.cur: Current ongoing transfer
> > + * @xferqueue.lock: Queue lock
> > + * @ibi: IBI structure
> > + * @ibi.num_slots: Number of slots available in @ibi.slots
> > + * @ibi.slots: Available IBI slots
> > + * @ibi.tbq_slot: To be queued IBI slot
> > + * @ibi.lock: IBI lock
> > + * @lock: Transfer lock, prevent concurrent daa/priv_xfer/ccc
> > + * @req_lock: protect between IBI isr and bus operation request
> > + */
> > +struct npcm_i3c_master {
> > + struct i3c_master_controller base;
> > + struct device *dev;
> > + void __iomem *regs;
> > + struct npcm_i3c_regs_save saved_regs;
> > + u32 free_slots;
> > + u8 addrs[NPCM_I3C_MAX_DEVS];
> > + struct i3c_dev_desc *descs[NPCM_I3C_MAX_DEVS];
> > + struct work_struct hj_work;
> > + int irq;
> > + struct clk *pclk;
> > + struct clk *fclk;
> > + struct {
> > + u32 i3c_pp_hi;
> > + u32 i3c_pp_lo;
> > + u32 i3c_pp_sda_rd_skew;
> > + u32 i3c_pp_sda_wr_skew;
> > + u32 i3c_od_hi;
> > + u32 i3c_od_lo;
> > + } scl_timing;
> > + struct {
> > + struct list_head list;
> > + struct npcm_i3c_xfer *cur;
> > + } xferqueue;
> > + struct {
> > + unsigned int num_slots;
> > + struct i3c_dev_desc **slots;
> > + struct i3c_ibi_slot *tbq_slot;
> > + /* Prevent races within IBI handlers */
> > + spinlock_t lock;
> > + } ibi;
> > + spinlock_t req_lock;
> > + struct mutex lock;
> > + struct dentry *debugfs;
> > +
> > + /* For DMA */
> > + void __iomem *dma_regs;
> > + void __iomem *dma_ctl_regs;
> > + bool use_dma;
> > + struct completion xfer_comp;
> > + char *dma_tx_buf;
> > + char *dma_rx_buf;
> > + dma_addr_t dma_tx_addr;
> > + dma_addr_t dma_rx_addr;
> > + struct npcm_dma_xfer_desc dma_xfer;
> > +
> > + bool en_hj;
> > +};
> > +
> > +/**
> > + * struct npcm_i3c_i2c_dev_data - Device specific data
> > + * @index: Index in the master tables corresponding to this device
> > + * @ibi: IBI slot index in the master structure
> > + * @ibi_pool: IBI pool associated to this device
> > + */
> > +struct npcm_i3c_i2c_dev_data {
> > + u8 index;
> > + int ibi;
> > + struct i3c_generic_ibi_pool *ibi_pool;
> > +};
> > +
> > +static DEFINE_MUTEX(npcm_i3c_dma_lock);
>
> Why this is outside driver private data - npcm_i3c_master?
>
> > +
> > +static int npcm_i3c_master_wait_for_complete(struct npcm_i3c_master *master);
> > +static void npcm_i3c_master_stop_dma(struct npcm_i3c_master *master);
> > +
> > +static void npcm_i3c_master_dma_lock(void)
> > +{
> > + mutex_lock(&npcm_i3c_dma_lock);
> > +}
> > +
> > +static void npcm_i3c_master_dma_unlock(void)
> > +{
> > + mutex_unlock(&npcm_i3c_dma_lock);
> > +}
>
>
> ...
>
>
> > +
> > +static void npcm_i3c_init_debugfs(struct platform_device *pdev,
> > + struct npcm_i3c_master *master)
> > +{
> > + if (!npcm_i3c_debugfs_dir) {
> > + npcm_i3c_debugfs_dir = debugfs_create_dir("npcm_i3c", NULL);
> > + if (!npcm_i3c_debugfs_dir)
> > + return;
> > + }
> > +
> > + master->debugfs = debugfs_create_dir(dev_name(&pdev->dev),
> > + npcm_i3c_debugfs_dir);
> > + if (!master->debugfs)
> > + return;
> > +
> > + debugfs_create_file("debug", 0444, master->debugfs, master, &debug_fops);
> > +}
> > +
> > +static int npcm_i3c_setup_dma(struct platform_device *pdev, struct npcm_i3c_master *master)
> > +{
> > + struct device *dev = &pdev->dev;
> > + u32 dma_conn, dma_ctl, reg_base;
> > +
> > + if (!of_property_read_bool(dev->of_node, "use-dma"))
> > + return 0;
> > +
> > + master->dma_regs = devm_platform_ioremap_resource_byname(pdev, "dma");
> > + if (IS_ERR(master->dma_regs))
> > + return 0;
> > +
> > + master->dma_ctl_regs = devm_platform_ioremap_resource_byname(pdev, "dma_ctl");
> > + if (IS_ERR(master->dma_ctl_regs))
>
>
> Hm? Why this is not a separate DMA controller?
>

I will implement a separate dma driver later, the dma configuration
and lock will be removed from i3c driver.

> > + return 0;
> > +
> > + /* DMA TX transfer width is 32 bits(MWDATAB width) for each byte sent to I3C bus */
> > + master->dma_tx_buf = dma_alloc_coherent(dev, MAX_DMA_COUNT * 4,
> > + &master->dma_tx_addr, GFP_KERNEL);
> > + if (!master->dma_tx_buf)
> > + return -ENOMEM;
> > +
> > + master->dma_rx_buf = dma_alloc_coherent(dev, MAX_DMA_COUNT,
> > + &master->dma_rx_addr, GFP_KERNEL);
> > + if (!master->dma_rx_buf) {
> > + dma_free_coherent(master->dev, MAX_DMA_COUNT * 4, master->dma_tx_buf,
> > + master->dma_tx_addr);
> > + return -ENOMEM;
> > + }
> > +
> > + /*
> > + * Set DMA channel connectivity
> > + * channel 0: I3C TX, channel 1: I3C RX
> > + */
> > + of_property_read_u32_index(dev->of_node, "reg", 0, &reg_base);
> > + dma_conn = NPCM_GDMA_MUX(reg_base);
> > + dma_ctl = GDMA_CH0_EN | GDMA_CH1_EN | (dma_conn + 1) << 16 | dma_conn;
> > + writel(dma_ctl, master->dma_ctl_regs);
> > + master->use_dma = true;
> > + dev_info(dev, "Using DMA (req_sel %d)\n", dma_conn);
> > +
> > + /*
> > + * Setup GDMA Channel for TX (Memory to I3C FIFO)
> > + */
> > + writel(master->dma_tx_addr, master->dma_regs + NPCM_GDMA_SRCB(DMA_CH_TX));
> > + writel(reg_base + NPCM_I3C_MWDATAB, master->dma_regs +
> > + NPCM_GDMA_DSTB(DMA_CH_TX));
> > + /*
> > + * Setup GDMA Channel for RX (I3C FIFO to Memory)
> > + */
> > + writel(reg_base + NPCM_I3C_MRDATAB, master->dma_regs +
> > + NPCM_GDMA_SRCB(DMA_CH_RX));
> > + writel(master->dma_rx_addr, master->dma_regs + NPCM_GDMA_DSTB(DMA_CH_RX));
> > +
> > + return 0;
> > +}
> > +
> > +static int npcm_i3c_master_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct npcm_i3c_master *master;
> > + struct reset_control *reset;
> > + u32 val;
> > + int ret;
> > +
> > + master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL);
> > + if (!master)
> > + return -ENOMEM;
> > +
> > + master->regs = devm_platform_ioremap_resource(pdev, 0);
> > + if (IS_ERR(master->regs))
> > + return PTR_ERR(master->regs);
> > +
> > + master->pclk = devm_clk_get(dev, "pclk");
> > + if (IS_ERR(master->pclk))
> > + return PTR_ERR(master->pclk);
> > +
> > + master->fclk = devm_clk_get(dev, "fast_clk");
> > + if (IS_ERR(master->fclk))
> > + return PTR_ERR(master->fclk);
> > +
> > + master->irq = platform_get_irq(pdev, 0);
> > + if (master->irq < 0)
> > + return master->irq;
> > +
> > + master->dev = dev;
> > +
> > + ret = npcm_i3c_master_prepare_clks(master);
> > + if (ret)
> > + return ret;
> > +
> > + reset = devm_reset_control_get(&pdev->dev, NULL);
>
> Use dev consistently.
>
> > + if (!IS_ERR(reset)) {
> > + reset_control_assert(reset);
> > + udelay(5);
> > + reset_control_deassert(reset);
> > + }
> > + INIT_WORK(&master->hj_work, npcm_i3c_master_hj_work);
> > + ret = devm_request_irq(dev, master->irq, npcm_i3c_master_irq_handler,
> > + IRQF_NO_SUSPEND, "npcm-i3c-irq", master);
> > + if (ret)
> > + goto err_disable_clks;
> > +
> > + master->free_slots = GENMASK(NPCM_I3C_MAX_DEVS - 1, 0);
> > +
> > + mutex_init(&master->lock);
> > + INIT_LIST_HEAD(&master->xferqueue.list);
> > +
> > + spin_lock_init(&master->req_lock);
> > + spin_lock_init(&master->ibi.lock);
> > + master->ibi.num_slots = NPCM_I3C_MAX_DEVS;
> > + master->ibi.slots = devm_kcalloc(&pdev->dev, master->ibi.num_slots,
>
> Once allocation with dev, other with pdev->dev...
>
> > + sizeof(*master->ibi.slots),
> > + GFP_KERNEL);
> > + if (!master->ibi.slots) {
> > + ret = -ENOMEM;
> > + goto err_disable_clks;
> > + }
> > +
> > + platform_set_drvdata(pdev, master);
> > +
> > + npcm_i3c_master_reset(master);
> > +
> > + if (of_property_read_bool(dev->of_node, "enable-hj"))
>
>
> > + master->en_hj = true;
> > + if (!of_property_read_u32(dev->of_node, "i3c-pp-scl-hi-period-ns", &val))
> > + master->scl_timing.i3c_pp_hi = val;
> > +
> > + if (!of_property_read_u32(dev->of_node, "i3c-pp-scl-lo-period-ns", &val))
> > + master->scl_timing.i3c_pp_lo = val;
> > +
> > + if (!of_property_read_u32(dev->of_node, "i3c-pp-sda-rd-skew", &val))
> > + master->scl_timing.i3c_pp_sda_rd_skew = val;
> > +
> > + if (!of_property_read_u32(dev->of_node, "i3c-pp-sda-wr-skew", &val))
> > + master->scl_timing.i3c_pp_sda_wr_skew = val;
> > +
> > + if (!of_property_read_u32(dev->of_node, "i3c-od-scl-hi-period-ns", &val))
> > + master->scl_timing.i3c_od_hi = val;
> > +
> > + if (!of_property_read_u32(dev->of_node, "i3c-od-scl-lo-period-ns", &val))
> > + master->scl_timing.i3c_od_lo = val;
> > +
> > + npcm_i3c_master_clear_merrwarn(master);
> > + npcm_i3c_master_flush_fifo(master);
> > +
> > + ret = npcm_i3c_setup_dma(pdev, master);
> > + if (ret)
> > + goto err_disable_clks;
> > +
> > + npcm_i3c_init_debugfs(pdev, master);
> > +
> > + /* Register the master */
> > + ret = i3c_master_register(&master->base, &pdev->dev,
> > + &npcm_i3c_master_ops, false);
> > + if (ret)
> > + goto err_disable_clks;
> > +
> > + if (master->en_hj) {
> > + dev_info(master->dev, "enable hot-join\n");
>
> Drop, not useful.
>
>
> > + npcm_i3c_master_enable_interrupts(master, NPCM_I3C_MINT_SLVSTART);
> > + }
> > + return 0;
> > +
> > + debugfs_remove_recursive(master->debugfs);
> > +
> > +err_disable_clks:
> > + npcm_i3c_master_unprepare_clks(master);
> > +
> > + return ret;
> > +}
> > +
> > +static int npcm_i3c_master_remove(struct platform_device *pdev)
> > +{
> > + struct npcm_i3c_master *master = platform_get_drvdata(pdev);
> > +
> > + /* Avoid ibi events during driver unbinding */
> > + writel(NPCM_I3C_MINT_SLVSTART, master->regs + NPCM_I3C_MINTCLR);
> > +
> > + debugfs_remove_recursive(master->debugfs);
> > +
> > + i3c_master_unregister(&master->base);
> > +
> > + if (master->use_dma) {
> > + dma_free_coherent(master->dev, MAX_DMA_COUNT * 4, master->dma_tx_buf,
> > + master->dma_tx_addr);
> > + dma_free_coherent(master->dev, MAX_DMA_COUNT, master->dma_rx_buf,
> > + master->dma_rx_addr);
> > + }
> > + return 0;
> > +}
> > +
> > +static const struct of_device_id npcm_i3c_master_of_match_tbl[] = {
> > + { .compatible = "nuvoton,npcm845-i3c" },
> > + { /* sentinel */ },
> > +};
> > +MODULE_DEVICE_TABLE(of, npcm_i3c_master_of_match_tbl);
> > +
> > +static struct platform_driver npcm_i3c_master = {
> > + .probe = npcm_i3c_master_probe,
> > + .remove = npcm_i3c_master_remove,
> > + .driver = {
> > + .name = "npcm845-i3c-master",
> > + .of_match_table = npcm_i3c_master_of_match_tbl,
> > + },
> > +};
> > +module_platform_driver(npcm_i3c_master);
> > +
> > +MODULE_AUTHOR("Stanley Chu <yschu@nuvoton.com>");
> > +MODULE_AUTHOR("James Chiang <cpchiang1@nuvoton.com>");
> > +MODULE_DESCRIPTION("Nuvoton NPCM845 I3C master driver");
> > +MODULE_LICENSE("GPL");
>
> Best regards,
> Krzysztof