Hi Chalapathi,
Looks good. Just some suggestions on readability and some
simplifications (see below).
Thanks,
Glenn
On Thu, 2024-05-16 at 11:33 -0500, Chalapathi V wrote:
> SPI controller device model supports a connection to a single SPI
> responder.
> This provide access to SPI seeproms, TPM, flash device and an ADC
> controller.
>
> All SPI function control is mapped into the SPI register space to
> enable full
> control by firmware. In this commit SPI configuration component is
> modelled
> which contains all SPI configuration and status registers as well as
> the hold
> registers for data to be sent or having been received.
>
> An existing QEMU SSI framework is used and SSI_BUS is created.
>
> Signed-off-by: Chalapathi V <chalapath...@linux.ibm.com>
> ---
> include/hw/ppc/pnv_xscom.h | 3 +
> include/hw/ssi/pnv_spi.h | 44 +++++++
> include/hw/ssi/pnv_spi_regs.h | 114 +++++++++++++++++
> hw/ppc/pnv_spi_controller.c | 228
> ++++++++++++++++++++++++++++++++++
> hw/ppc/Kconfig | 1 +
> hw/ppc/meson.build | 1 +
> hw/ppc/trace-events | 6 +
> 7 files changed, 397 insertions(+)
> create mode 100644 include/hw/ssi/pnv_spi.h
> create mode 100644 include/hw/ssi/pnv_spi_regs.h
> create mode 100644 hw/ppc/pnv_spi_controller.c
>
> diff --git a/include/hw/ppc/pnv_xscom.h b/include/hw/ppc/pnv_xscom.h
> index 6209e18492..a77b97f9b1 100644
> --- a/include/hw/ppc/pnv_xscom.h
> +++ b/include/hw/ppc/pnv_xscom.h
> @@ -194,6 +194,9 @@ struct PnvXScomInterfaceClass {
> #define PNV10_XSCOM_PEC_PCI_BASE 0x8010800 /* index goes upwards
> ... */
> #define PNV10_XSCOM_PEC_PCI_SIZE 0x200
>
> +#define PNV10_XSCOM_PIB_SPIC_BASE 0xc0000
> +#define PNV10_XSCOM_PIB_SPIC_SIZE 0x20
> +
> void pnv_xscom_init(PnvChip *chip, uint64_t size, hwaddr addr);
> int pnv_dt_xscom(PnvChip *chip, void *fdt, int root_offset,
> uint64_t xscom_base, uint64_t xscom_size,
> diff --git a/include/hw/ssi/pnv_spi.h b/include/hw/ssi/pnv_spi.h
> new file mode 100644
> index 0000000000..244ee1cfc0
> --- /dev/null
> +++ b/include/hw/ssi/pnv_spi.h
> @@ -0,0 +1,44 @@
> +/*
> + * QEMU PowerPC SPI Controller model
> + *
> + * Copyright (c) 2024, IBM Corporation.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * This model Supports a connection to a single SPI responder.
> + * Introduced for P10 to provide access to SPI seeproms, TPM, flash
> device
> + * and an ADC controller.
> + */
> +#include "hw/ssi/ssi.h"
> +
> +#ifndef PPC_PNV_SPI_CONTROLLER_H
> +#define PPC_PNV_SPI_CONTROLLER_H
> +
> +#define TYPE_PNV_SPI_CONTROLLER "pnv-spi-controller"
> +#define PNV_SPICONTROLLER(obj) \
> + OBJECT_CHECK(PnvSpiController, (obj),
> TYPE_PNV_SPI_CONTROLLER)
> +
> +#define SPI_CONTROLLER_REG_SIZE 8
> +
> +#define TYPE_PNV_SPI_BUS "pnv-spi-bus"
> +typedef struct PnvSpiController {
> + SysBusDevice parent_obj;
> +
> + SSIBus *ssi_bus;
> + qemu_irq *cs_line;
> + MemoryRegion xscom_spic_regs;
> + /* SPI controller object number */
> + uint32_t spic_num;
> +
Would it be better to make these into an array of registers? It would
probably simplify your read/write functions.
> + /* SPI Controller registers */
> + uint64_t error_reg;
> + uint64_t counter_config_reg;
> + uint64_t config_reg1;
> + uint64_t clock_config_reset_control;
> + uint64_t memory_mapping_reg;
> + uint64_t transmit_data_reg;
> + uint64_t receive_data_reg;
> + uint8_t sequencer_operation_reg[SPI_CONTROLLER_REG_SIZE]
> ;
> + uint64_t status_reg;
> +} PnvSpiController;
> +#endif /* PPC_PNV_SPI_CONTROLLER_H */
> diff --git a/include/hw/ssi/pnv_spi_regs.h
> b/include/hw/ssi/pnv_spi_regs.h
> new file mode 100644
> index 0000000000..6f613aca5e
> --- /dev/null
> +++ b/include/hw/ssi/pnv_spi_regs.h
> @@ -0,0 +1,114 @@
> +/*
> + * QEMU PowerPC SPI Controller model
> + *
> + * Copyright (c) 2023, IBM Corporation.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#ifndef SPI_CONTROLLER_REGS_H
> +#define SPI_CONTROLLER_REGS_H
> +
In order to improve readability, I think all of these register/field
names should be shortened so that code fits into the 80 char limit more
easily. I think they should also be prefixed with SPI_*. Probably
don't need the "REG" in the middle of the field names either, just keep
it in the register names? Possible suggestions follow to give a better
idea of what I'm talking about...
> +/* Error Register */
> +#define ERROR_REG 0x00
> +
I would change this to something like SPI_CTR_CFG_REG.
> +/* counter_config_reg */
> +#define COUNTER_CONFIG_REG 0x01
SPI_CTR_CFG_N1/N2
> +#define COUNTER_CONFIG_REG_SHIFT_COUNT_N1 PPC_BITMASK(0, 7)
> +#define COUNTER_CONFIG_REG_SHIFT_COUNT_N2 PPC_BITMASK(8, 15)
SPI_CTR_CFG_CMP1/CMP2
> +#define COUNTER_CONFIG_REG_COUNT_COMPARE1 PPC_BITMASK(24, 31)
> +#define COUNTER_CONFIG_REG_COUNT_COMPARE2 PPC_BITMASK(32, 39)
SPI_CTR_CFG_N1_CTRL
> +#define COUNTER_CONFIG_REG_N1_COUNT_CONTROL PPC_BITMASK(48, 51)
> +#define COUNTER_CONFIG_REG_N2_COUNT_CONTROL PPC_BITMASK(52, 55)
> +
> +/* config_reg */
> +#define CONFIG_REG1 0x02
> +
> +/* clock_config_reset_control_ecc_enable_reg */
SPI_CLK_CFG_REG
> +#define CLOCK_CONFIG_REG 0x03
SPI_CLK_CFG_HARD_RST
> +#define CLOCK_CONFIG_RESET_CONTROL_HARD_RESET 0x0084000000000000;
SPI_CLK_CFG_RST_CTRL
> +#define CLOCK_CONFIG_REG_RESET_CONTROL PPC_BITMASK(24, 27)
> +#define CLOCK_CONFIG_REG_ECC_CONTROL PPC_BITMASK(28, 30)
> +
> +/* memory_mapping_reg */
SPI_MM_REG
> +#define MEMORY_MAPPING_REG 0x04
SPI_MM_BASE_ADDR
> +#define MEMORY_MAPPING_REG_MMSPISM_BASE_ADDR PPC_BITMASK(0, 15)
> +#define MEMORY_MAPPING_REG_MMSPISM_ADDR_MASK PPC_BITMASK(16, 31)
> +#define MEMORY_MAPPING_REG_RDR_MATCH_VAL PPC_BITMASK(32, 47)
> +#define MEMORY_MAPPING_REG_RDR_MATCH_MASK PPC_BITMASK(48, 63)
> +
> +/* transmit_data_reg */
SPI_XMIT_DATA_REG
> +#define TRANSMIT_DATA_REG 0x05
> +
> +/* receive_data_reg */
SPI_RCV_DATA_REG
> +#define RECEIVE_DATA_REG 0x06
> +
SPI_SEQ_OP_REG
> +/* sequencer_operation_reg */
> +#define SEQUENCER_OPERATION_REG 0x07
> +
> +/* status_reg */
SPI_STS_REG
> +#define STATUS_REG 0x08
SPI_STS_RDR_FULL
> +#define STATUS_REG_RDR_FULL PPC_BIT(0)
> +#define STATUS_REG_RDR_OVERRUN PPC_BIT(1)
> +#define STATUS_REG_RDR_UNDERRUN PPC_BIT(2)
> +#define STATUS_REG_TDR_FULL PPC_BIT(4)
> +#define STATUS_REG_TDR_OVERRUN PPC_BIT(5)
> +#define STATUS_REG_TDR_UNDERRUN PPC_BIT(6)
> +#define STATUS_REG_SEQUENCER_FSM PPC_BITMASK(8, 15)
> +#define STATUS_REG_SHIFTER_FSM PPC_BITMASK(16, 27)
> +#define STATUS_REG_SEQUENCER_INDEX PPC_BITMASK(28, 31)
> +#define STATUS_REG_GENERAL_SPI_STATUS PPC_BITMASK(32, 63)
> +#define STATUS_REG_RDR PPC_BITMASK(1, 3)
> +#define STATUS_REG_TDR PPC_BITMASK(5, 7)
> +
> +/*
> + * Shifter states
> + *
> + * These are the same values defined for the Shifter FSM field of
> the
> + * status register. It's a 12 bit field so we will represent it as
> three
> + * nibbles in the constants.
> + *
> + * These are shifter_fsm values
> + *
> + * Status reg bits 16-27 -> field bits 0-11
> + * bits 0,1,2,5 unused/reserved
> + * bit 4 crc shift in (unused)
> + * bit 8 crc shift out (unused)
> + */
> +
> +#define FSM_DONE 0x100 /* bit 3 */
> +#define FSM_SHIFT_N2 0x020 /* bit 6 */
> +#define FSM_WAIT 0x010 /* bit 7 */
> +#define FSM_SHIFT_N1 0x004 /* bit 9 */
> +#define FSM_START 0x002 /* bit 10 */
> +#define FSM_IDLE 0x001 /* bit 11 */
> +
> +/*
> + * Sequencer states
> + *
> + * These are sequencer_fsm values
> + *
> + * Status reg bits 8-15 -> field bits 0-7
> + * bits 0-3 unused/reserved
> + *
> + */
> +#define SEQ_STATE_INDEX_INCREMENT 0x08 /* bit 4 */
> +#define SEQ_STATE_EXECUTE 0x04 /* bit 5 */
> +#define SEQ_STATE_DECODE 0x02 /* bit 6 */
> +#define SEQ_STATE_IDLE 0x01 /* bit 7 */
> +
> +/*
> + * These are the supported sequencer operations.
> + * Only the upper nibble is significant because for many operations
> + * the lower nibble is a variable specific to the operation.
> + */
> +#define SEQ_OP_STOP 0x00
> +#define SEQ_OP_SELECT_SLAVE 0x10
> +#define SEQ_OP_SHIFT_N1 0x30
> +#define SEQ_OP_SHIFT_N2 0x40
> +#define SEQ_OP_BRANCH_IFNEQ_RDR 0x60
> +#define SEQ_OP_TRANSFER_TDR 0xC0
> +#define SEQ_OP_BRANCH_IFNEQ_INC_1 0xE0
> +#define SEQ_OP_BRANCH_IFNEQ_INC_2 0xF0
> +
> +#endif
> diff --git a/hw/ppc/pnv_spi_controller.c
> b/hw/ppc/pnv_spi_controller.c
> new file mode 100644
> index 0000000000..11b119cf0f
> --- /dev/null
> +++ b/hw/ppc/pnv_spi_controller.c
> @@ -0,0 +1,228 @@
> +/*
> + * QEMU PowerPC SPI Controller model
> + *
> + * Copyright (c) 2024, IBM Corporation.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/log.h"
> +#include "hw/qdev-properties.h"
> +#include "hw/ppc/pnv_xscom.h"
> +#include "hw/ssi/pnv_spi.h"
> +#include "hw/ssi/pnv_spi_regs.h"
> +#include "hw/ssi/ssi.h"
> +#include "hw/ppc/fdt.h"
> +#include <libfdt.h>
> +#include <math.h>
> +#include "hw/irq.h"
> +#include "trace.h"
> +
> +static uint64_t pnv_spi_controller_read(void *opaque, hwaddr addr,
> + unsigned size)
> +{
> + PnvSpiController *s = PNV_SPICONTROLLER(opaque);
> + uint32_t reg = addr >> 3;
> + uint64_t val = ~0ull;
> +
For the most part, this switch statement is simply converting the
register number into a register field name. This is where, if the
registers were kept in an array, you could remove many of the cases and
just have special cases for registers that require special behavior.
> + switch (reg) {
> + case ERROR_REG:
> + val = s->error_reg;
> + break;
> + case COUNTER_CONFIG_REG:
> + val = s->counter_config_reg;
> + break;
> + case CONFIG_REG1:
> + val = s->config_reg1;
> + break;
> + case CLOCK_CONFIG_REG:
> + val = s->clock_config_reset_control;
> + break;
> + case MEMORY_MAPPING_REG:
> + val = s->memory_mapping_reg;
> + break;
> + case TRANSMIT_DATA_REG:
> + val = s->transmit_data_reg;
> + break;
> + case RECEIVE_DATA_REG:
> + val = s->receive_data_reg;
> + trace_pnv_spi_read_RDR(val);
> + s->status_reg = SETFIELD(STATUS_REG_RDR_FULL, s->status_reg,
> 0);
> + break;
> + case SEQUENCER_OPERATION_REG:
> + val = 0;
> + for (int i = 0; i < SPI_CONTROLLER_REG_SIZE; i++) {
> + val = (val << 8) | s->sequencer_operation_reg[i];
> + }
> + break;
> + case STATUS_REG:
> + val = s->status_reg;
> + break;
> + default:
> + qemu_log_mask(LOG_GUEST_ERROR, "spi_controller_regs: Invalid
> xscom "
> + "read at 0x%08x\n", reg);
> + }
> +
> + trace_pnv_spi_read(addr, val);
> + return val;
> +}
> +
> +static void pnv_spi_controller_write(void *opaque, hwaddr addr,
> + uint64_t val, unsigned size)
> +{
> + PnvSpiController *s = PNV_SPICONTROLLER(opaque);
> + uint32_t reg = addr >> 3;
> +
> + trace_pnv_spi_write(addr, val);
> +
> + switch (reg) {
> + case ERROR_REG:
> + s->error_reg = val;
> + break;
> + case COUNTER_CONFIG_REG:
> + s->counter_config_reg = val;
> + break;
> + case CONFIG_REG1:
> + s->config_reg1 = val;
> + break;
> + case CLOCK_CONFIG_REG:
> + /*
> + * To reset the SPI controller write the sequence 0x5 0xA to
> + * reset_control field
> + */
This is one of the places where shortened register/field names would
help. Also, I think you should combine these two if/else statements
into a single if/else statement using the && operator.
> + if (GETFIELD(CLOCK_CONFIG_REG_RESET_CONTROL,
> + s->clock_config_reset_control) ==
> 0x5) {
> + if (GETFIELD(CLOCK_CONFIG_REG_RESET_CONTROL, val) ==
> 0xA) {
> + /* SPI controller reset sequence completed,
> resetting */
> + s->clock_config_reset_control =
> + CLOCK_CONFIG_RESET_CONTROL_HARD_RES
> ET;
> + } else {
> + s->clock_config_reset_control = val;
> + }
> + } else {
> + s->clock_config_reset_control = val;
> + }
> + break;
> + case MEMORY_MAPPING_REG:
> + s->memory_mapping_reg = val;
> + break;
> + case TRANSMIT_DATA_REG:
> + /*
> + * Writing to the transmit data register causes the transmit
> data
> + * register full status bit in the status register to be
> set. Writing
> + * when the transmit data register full status bit is
> already set
> + * causes a "Resource Not Available" condition. This is not
> possible
> + * in the model since writes to this register are not
> asynchronous to
> + * the operation sequence like it would be in hardware.
> + */
> + s->transmit_data_reg = val;
> + trace_pnv_spi_write_TDR(val);
> + s->status_reg = SETFIELD(STATUS_REG_TDR_FULL, s->status_reg,
> 1);
> + s->status_reg = SETFIELD(STATUS_REG_TDR_UNDERRUN, s-
> >status_reg, 0);
> + break;
> + case RECEIVE_DATA_REG:
> + s->receive_data_reg = val;
> + break;
> + case SEQUENCER_OPERATION_REG:
> + for (int i = 0; i < SPI_CONTROLLER_REG_SIZE; i++) {
> + s->sequencer_operation_reg[i] = (val >> (56 - i * 8)) &
> 0xFF;
> + }
> + break;
> + case STATUS_REG:
> + /* other fields are ignore_write */
> + s->status_reg = SETFIELD(STATUS_REG_RDR_OVERRUN, s-
> >status_reg,
> + GETFIELD(STATUS_REG_RDR, val));
> + s->status_reg = SETFIELD(STATUS_REG_TDR_OVERRUN, s-
> >status_reg,
> + GETFIELD(STATUS_REG_TDR, val));
> + break;
> + default:
> + qemu_log_mask(LOG_GUEST_ERROR, "spi_controller_regs: Invalid
> xscom "
> + "write at 0x%08x\n", reg);
> + }
> + return;
> +}
> +
> +static const MemoryRegionOps pnv_spi_controller_xscom_ops = {
> + .read = pnv_spi_controller_read,
> + .write = pnv_spi_controller_write,
> + .valid.min_access_size = 8,
> + .valid.max_access_size = 8,
> + .impl.min_access_size = 8,
> + .impl.max_access_size = 8,
> + .endianness = DEVICE_BIG_ENDIAN,
> +};
> +
> +static Property pnv_spi_controller_properties[] = {
> + DEFINE_PROP_UINT32("spic_num", PnvSpiController, spic_num, 0),
> + DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void pnv_spi_controller_realize(DeviceState *dev, Error
> **errp)
> +{
> + PnvSpiController *s = PNV_SPICONTROLLER(dev);
> + g_autofree char *name = g_strdup_printf(TYPE_PNV_SPI_BUS ".%d",
> + s->spic_num);
> + s->ssi_bus = ssi_create_bus(dev, name);
> + s->cs_line = g_new0(qemu_irq, 1);
> + qdev_init_gpio_out_named(DEVICE(s), s->cs_line, "cs", 1);
> +
> + /* spi controller scoms */
> + pnv_xscom_region_init(&s->xscom_spic_regs, OBJECT(s),
> + &pnv_spi_controller_xscom_ops, s,
> + "xscom-spi-controller-regs",
> + PNV10_XSCOM_PIB_SPIC_SIZE);
> +}
> +
> +static int pnv_spi_controller_dt_xscom(PnvXScomInterface *dev, void
> *fdt,
> + int offset)
> +{
> + PnvSpiController *s = PNV_SPICONTROLLER(dev);
> + g_autofree char *name;
> + int s_offset;
> + const char compat[] = "ibm,power10-spi_controller";
> + uint32_t spic_pcba = PNV10_XSCOM_PIB_SPIC_BASE +
> + s->spic_num * PNV10_XSCOM_PIB_SPIC_SIZE;
> + uint32_t reg[] = {
> + cpu_to_be32(spic_pcba),
> + cpu_to_be32(PNV10_XSCOM_PIB_SPIC_SIZE)
> + };
> + name = g_strdup_printf("spi_controller@%x", spic_pcba);
> + s_offset = fdt_add_subnode(fdt, offset, name);
> + _FDT(s_offset);
> +
> + _FDT(fdt_setprop(fdt, s_offset, "reg", reg, sizeof(reg)));
> + _FDT(fdt_setprop(fdt, s_offset, "compatible", compat,
> sizeof(compat)));
> + _FDT((fdt_setprop_cell(fdt, s_offset, "spic_num#", s-
> >spic_num)));
> + return 0;
> +}
> +
> +static void pnv_spi_controller_class_init(ObjectClass *klass, void
> *data)
> +{
> + DeviceClass *dc = DEVICE_CLASS(klass);
> + PnvXScomInterfaceClass *xscomc =
> PNV_XSCOM_INTERFACE_CLASS(klass);
> +
> + xscomc->dt_xscom = pnv_spi_controller_dt_xscom;
> +
> + dc->desc = "PowerNV SPI Controller";
> + dc->realize = pnv_spi_controller_realize;
> + device_class_set_props(dc, pnv_spi_controller_properties);
> +}
> +
> +static const TypeInfo pnv_spi_controller_info = {
> + .name = TYPE_PNV_SPI_CONTROLLER,
> + .parent = TYPE_SYS_BUS_DEVICE,
> + .instance_size = sizeof(PnvSpiController),
> + .class_init = pnv_spi_controller_class_init,
> + .interfaces = (InterfaceInfo[]) {
> + { TYPE_PNV_XSCOM_INTERFACE },
> + { }
> + }
> +};
> +
> +static void pnv_spi_controller_register_types(void)
> +{
> + type_register_static(&pnv_spi_controller_info);
> +}
> +
> +type_init(pnv_spi_controller_register_types);
> diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
> index 78f83e78ce..6f9670b377 100644
> --- a/hw/ppc/Kconfig
> +++ b/hw/ppc/Kconfig
> @@ -39,6 +39,7 @@ config POWERNV
> select PCI_POWERNV
> select PCA9552
> select PCA9554
> + select SSI
>
> config PPC405
> bool
> diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build
> index d096636ee7..68fadbae7b 100644
> --- a/hw/ppc/meson.build
> +++ b/hw/ppc/meson.build
> @@ -56,6 +56,7 @@ ppc_ss.add(when: 'CONFIG_POWERNV', if_true: files(
> 'pnv_pnor.c',
> 'pnv_nest_pervasive.c',
> 'pnv_n1_chiplet.c',
> + 'pnv_spi_controller.c',
> ))
> # PowerPC 4xx boards
> ppc_ss.add(when: 'CONFIG_PPC405', if_true: files(
> diff --git a/hw/ppc/trace-events b/hw/ppc/trace-events
> index bf29bbfd4b..b8e494ffc5 100644
> --- a/hw/ppc/trace-events
> +++ b/hw/ppc/trace-events
> @@ -110,6 +110,12 @@ pnv_sbe_cmd_timer_stop(void) ""
> pnv_sbe_cmd_timer_expired(void) ""
> pnv_sbe_msg_recv(uint16_t cmd, uint16_t seq, uint16_t ctrl_flags)
> "cmd 0x%" PRIx16 " seq %"PRIu16 " ctrl_flags 0x%" PRIx16
>
> +#pnv_spi_controller.c
> +pnv_spi_read(uint64_t addr, uint64_t val) "addr 0x%" PRIx64 " val
> 0x%" PRIx64
> +pnv_spi_write(uint64_t addr, uint64_t val) "addr 0x%" PRIx64 " val
> 0x%" PRIx64
> +pnv_spi_read_RDR(uint64_t val) "data extracted = 0x%" PRIx64
> +pnv_spi_write_TDR(uint64_t val) "being written, data written = 0x%"
> PRIx64
> +
> # ppc.c
> ppc_tb_adjust(uint64_t offs1, uint64_t offs2, int64_t diff, int64_t
> seconds) "adjusted from 0x%"PRIx64" to 0x%"PRIx64", diff %"PRId64"
> (%"PRId64"s)"
> ppc_tb_load(uint64_t tb) "tb 0x%016" PRIx64
