Re: [PATCH 2/3] fsi: occ: Add support for P10

From: Guenter Roeck
Date: Sun Jul 19 2020 - 18:13:06 EST


On Fri, May 01, 2020 at 10:08:32AM -0500, Eddie James wrote:
> The P10 OCC has a different SRAM address for the command and response
> buffers. In addition, the SBE commands to access the SRAM have changed
> format. Add versioning to the driver to handle these differences.
>
> Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>

I don't recall seeing a maintainer Ack for this patch, nor any response
at all. I'd be happy to apply the patch through hwmon, but I would need
an Ack from a maintainer.

Thanks,
Guenter

> ---
> drivers/fsi/fsi-occ.c | 126 ++++++++++++++++++++++++++++++------------
> 1 file changed, 92 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/fsi/fsi-occ.c b/drivers/fsi/fsi-occ.c
> index 7da9c81759ac..942eff4032b0 100644
> --- a/drivers/fsi/fsi-occ.c
> +++ b/drivers/fsi/fsi-occ.c
> @@ -14,6 +14,7 @@
> #include <linux/mutex.h>
> #include <linux/fsi-occ.h>
> #include <linux/of.h>
> +#include <linux/of_device.h>
> #include <linux/platform_device.h>
> #include <linux/sched.h>
> #include <linux/slab.h>
> @@ -24,8 +25,13 @@
> #define OCC_CMD_DATA_BYTES 4090
> #define OCC_RESP_DATA_BYTES 4089
>
> -#define OCC_SRAM_CMD_ADDR 0xFFFBE000
> -#define OCC_SRAM_RSP_ADDR 0xFFFBF000
> +#define OCC_P9_SRAM_CMD_ADDR 0xFFFBE000
> +#define OCC_P9_SRAM_RSP_ADDR 0xFFFBF000
> +
> +#define OCC_P10_SRAM_CMD_ADDR 0xFFFFD000
> +#define OCC_P10_SRAM_RSP_ADDR 0xFFFFE000
> +
> +#define OCC_P10_SRAM_MODE 0x58 /* Normal mode, OCB channel 2 */
>
> /*
> * Assume we don't have much FFDC, if we do we'll overflow and
> @@ -37,11 +43,14 @@
> #define OCC_TIMEOUT_MS 1000
> #define OCC_CMD_IN_PRG_WAIT_MS 50
>
> +enum versions { occ_p9, occ_p10 };
> +
> struct occ {
> struct device *dev;
> struct device *sbefifo;
> char name[32];
> int idx;
> + enum versions version;
> struct miscdevice mdev;
> struct mutex occ_lock;
> };
> @@ -235,29 +244,43 @@ static int occ_verify_checksum(struct occ_response *resp, u16 data_length)
> return 0;
> }
>
> -static int occ_getsram(struct occ *occ, u32 address, void *data, ssize_t len)
> +static int occ_getsram(struct occ *occ, u32 offset, void *data, ssize_t len)
> {
> u32 data_len = ((len + 7) / 8) * 8; /* must be multiples of 8 B */
> - size_t resp_len, resp_data_len;
> - __be32 *resp, cmd[5];
> - int rc;
> + size_t cmd_len, resp_len, resp_data_len;
> + __be32 *resp, cmd[6];
> + int idx = 0, rc;
>
> /*
> * Magic sequence to do SBE getsram command. SBE will fetch data from
> * specified SRAM address.
> */
> - cmd[0] = cpu_to_be32(0x5);
> + switch (occ->version) {
> + default:
> + case occ_p9:
> + cmd_len = 5;
> + cmd[2] = cpu_to_be32(1); /* Normal mode */
> + cmd[3] = cpu_to_be32(OCC_P9_SRAM_RSP_ADDR + offset);
> + break;
> + case occ_p10:
> + idx = 1;
> + cmd_len = 6;
> + cmd[2] = cpu_to_be32(OCC_P10_SRAM_MODE);
> + cmd[3] = 0;
> + cmd[4] = cpu_to_be32(OCC_P10_SRAM_RSP_ADDR + offset);
> + break;
> + }
> +
> + cmd[0] = cpu_to_be32(cmd_len);
> cmd[1] = cpu_to_be32(SBEFIFO_CMD_GET_OCC_SRAM);
> - cmd[2] = cpu_to_be32(1);
> - cmd[3] = cpu_to_be32(address);
> - cmd[4] = cpu_to_be32(data_len);
> + cmd[4 + idx] = cpu_to_be32(data_len);
>
> resp_len = (data_len >> 2) + OCC_SBE_STATUS_WORDS;
> resp = kzalloc(resp_len << 2, GFP_KERNEL);
> if (!resp)
> return -ENOMEM;
>
> - rc = sbefifo_submit(occ->sbefifo, cmd, 5, resp, &resp_len);
> + rc = sbefifo_submit(occ->sbefifo, cmd, cmd_len, resp, &resp_len);
> if (rc)
> goto free;
>
> @@ -287,20 +310,21 @@ static int occ_getsram(struct occ *occ, u32 address, void *data, ssize_t len)
> return rc;
> }
>
> -static int occ_putsram(struct occ *occ, u32 address, const void *data,
> - ssize_t len)
> +static int occ_putsram(struct occ *occ, const void *data, ssize_t len)
> {
> size_t cmd_len, buf_len, resp_len, resp_data_len;
> u32 data_len = ((len + 7) / 8) * 8; /* must be multiples of 8 B */
> __be32 *buf;
> - int rc;
> + int idx = 0, rc;
> +
> + cmd_len = (occ->version == occ_p10) ? 6 : 5;
>
> /*
> * We use the same buffer for command and response, make
> * sure it's big enough
> */
> resp_len = OCC_SBE_STATUS_WORDS;
> - cmd_len = (data_len >> 2) + 5;
> + cmd_len += data_len >> 2;
> buf_len = max(cmd_len, resp_len);
> buf = kzalloc(buf_len << 2, GFP_KERNEL);
> if (!buf)
> @@ -312,11 +336,23 @@ static int occ_putsram(struct occ *occ, u32 address, const void *data,
> */
> buf[0] = cpu_to_be32(cmd_len);
> buf[1] = cpu_to_be32(SBEFIFO_CMD_PUT_OCC_SRAM);
> - buf[2] = cpu_to_be32(1);
> - buf[3] = cpu_to_be32(address);
> - buf[4] = cpu_to_be32(data_len);
>
> - memcpy(&buf[5], data, len);
> + switch (occ->version) {
> + default:
> + case occ_p9:
> + buf[2] = cpu_to_be32(1); /* Normal mode */
> + buf[3] = cpu_to_be32(OCC_P9_SRAM_CMD_ADDR);
> + break;
> + case occ_p10:
> + idx = 1;
> + buf[2] = cpu_to_be32(OCC_P10_SRAM_MODE);
> + buf[3] = 0;
> + buf[4] = cpu_to_be32(OCC_P10_SRAM_CMD_ADDR);
> + break;
> + }
> +
> + buf[4 + idx] = cpu_to_be32(data_len);
> + memcpy(&buf[5 + idx], data, len);
>
> rc = sbefifo_submit(occ->sbefifo, buf, cmd_len, buf, &resp_len);
> if (rc)
> @@ -356,21 +392,35 @@ static int occ_putsram(struct occ *occ, u32 address, const void *data,
> static int occ_trigger_attn(struct occ *occ)
> {
> __be32 buf[OCC_SBE_STATUS_WORDS];
> - size_t resp_len, resp_data_len;
> - int rc;
> + size_t cmd_len, resp_len, resp_data_len;
> + int idx = 0, rc;
>
> - BUILD_BUG_ON(OCC_SBE_STATUS_WORDS < 7);
> + BUILD_BUG_ON(OCC_SBE_STATUS_WORDS < 8);
> resp_len = OCC_SBE_STATUS_WORDS;
>
> - buf[0] = cpu_to_be32(0x5 + 0x2); /* Chip-op length in words */
> + switch (occ->version) {
> + default:
> + case occ_p9:
> + cmd_len = 7;
> + buf[2] = cpu_to_be32(3); /* Circular mode */
> + buf[3] = 0;
> + break;
> + case occ_p10:
> + idx = 1;
> + cmd_len = 8;
> + buf[2] = cpu_to_be32(0xd0); /* Circular mode, OCB Channel 1 */
> + buf[3] = 0;
> + buf[4] = 0;
> + break;
> + }
> +
> + buf[0] = cpu_to_be32(cmd_len); /* Chip-op length in words */
> buf[1] = cpu_to_be32(SBEFIFO_CMD_PUT_OCC_SRAM);
> - buf[2] = cpu_to_be32(0x3); /* Mode: Circular */
> - buf[3] = cpu_to_be32(0x0); /* Address: ignore in mode 3 */
> - buf[4] = cpu_to_be32(0x8); /* Data length in bytes */
> - buf[5] = cpu_to_be32(0x20010000); /* Trigger OCC attention */
> - buf[6] = 0;
> + buf[4 + idx] = cpu_to_be32(8); /* Data length in bytes */
> + buf[5 + idx] = cpu_to_be32(0x20010000); /* Trigger OCC attention */
> + buf[6 + idx] = 0;
>
> - rc = sbefifo_submit(occ->sbefifo, buf, 7, buf, &resp_len);
> + rc = sbefifo_submit(occ->sbefifo, buf, cmd_len, buf, &resp_len);
> if (rc)
> goto error;
>
> @@ -429,7 +479,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
>
> /* Extract the seq_no from the command (first byte) */
> seq_no = *(const u8 *)request;
> - rc = occ_putsram(occ, OCC_SRAM_CMD_ADDR, request, req_len);
> + rc = occ_putsram(occ, request, req_len);
> if (rc)
> goto done;
>
> @@ -440,7 +490,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
> /* Read occ response header */
> start = jiffies;
> do {
> - rc = occ_getsram(occ, OCC_SRAM_RSP_ADDR, resp, 8);
> + rc = occ_getsram(occ, 0, resp, 8);
> if (rc)
> goto done;
>
> @@ -476,8 +526,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
> /* Grab the rest */
> if (resp_data_length > 1) {
> /* already got 3 bytes resp, also need 2 bytes checksum */
> - rc = occ_getsram(occ, OCC_SRAM_RSP_ADDR + 8,
> - &resp->data[3], resp_data_length - 1);
> + rc = occ_getsram(occ, 8, &resp->data[3], resp_data_length - 1);
> if (rc)
> goto done;
> }
> @@ -508,6 +557,7 @@ static int occ_probe(struct platform_device *pdev)
> struct occ *occ;
> struct platform_device *hwmon_dev;
> struct device *dev = &pdev->dev;
> + const void *md = of_device_get_match_data(dev);
> struct platform_device_info hwmon_dev_info = {
> .parent = dev,
> .name = "occ-hwmon",
> @@ -517,6 +567,7 @@ static int occ_probe(struct platform_device *pdev)
> if (!occ)
> return -ENOMEM;
>
> + occ->version = (enum versions)md;
> occ->dev = dev;
> occ->sbefifo = dev->parent;
> mutex_init(&occ->occ_lock);
> @@ -575,7 +626,14 @@ static int occ_remove(struct platform_device *pdev)
> }
>
> static const struct of_device_id occ_match[] = {
> - { .compatible = "ibm,p9-occ" },
> + {
> + .compatible = "ibm,p9-occ",
> + .data = (void *)occ_p9
> + },
> + {
> + .compatible = "ibm,p10-occ",
> + .data = (void *)occ_p10
> + },
> { },
> };
>