[Skiboot] [PATCH V6 3/3] occ: Add support for Version 0x90 OCC_OPAL shared memory region
Shilpasri G Bhat
shilpa.bhat at linux.vnet.ibm.com
Thu Feb 2 17:57:04 AEDT 2017
Hi,
On 02/02/2017 10:31 AM, Stewart Smith wrote:
> Shilpasri G Bhat <shilpa.bhat at linux.vnet.ibm.com> writes:
>> This patch enables pstate table parsing support for P9. It
>> introduces below device tree changes.
>> - Add a new node per chip in /ibm,opal/power-mgt called occ.
>> occ at 3ffd9f8000 {
>> reg = <0x3f 0xfd9f8000>;
>> ibm,chip-id = <0x0>;
>> ibm,pstate-vdds = <0x4e4e4f4f 0x4f505152 0x53545556
>> 0x5758595a 0x5b5c5d5e 0x5f606162 0x63646565 0x66676868
>> 0x696a6a6b 0x6c6d6d6e 0x6f6f7071 0x72727374 0x74757677
>> 0x7778797a 0x7a7b7c7c>;
>> ibm,pstate-vcss = <0x4446484a 0x4c4e4f50 0x50515253
>> 0x54555556 0x5758595a 0x5a5b5c5d 0x5d5e5e5e 0x5e5f5f5f
>> 0x5f606060 0x61616161 0x62626263 0x63636364 0x64646465
>> 0x65656666 0x66666767>;
>> ibm,pstate-core-max = <0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0>;
>> phandle = <0x10000326>;
>> };
>
> Ben - any thoughts on device tree layout for ^ ?
>
> I'm wondering if we need it per chip or if the information in the
> ibm,pstate-* is mostly common, and we should just point to it rather
> than have a copy per chip?
>
>> - Move VID (ibm,pstate-vdds, ibm,pstate-vcss) and max pstate for
>> #n active cores array (ibm,pstate-core-max) in to the new per-chip
>> /ibm,opal/power-mgt/occ node as these properties are unique to
>> chip.
>> - WOF is supported from version 0x02. Till now we have been adding
>> max ultra-turbo pstate(ibm,pstate-ultra-turbo), max turbo pstate
>> (ibm,pstate-turbo) and max pstate-per-n-core (ibm,pstate-core-max)
>> only when WOF is enabled. This patch will add these properties
>> even when WOF is disabled. When WOF is disabled max ultra turbo pstate
>> equals to max turbo pstate and max pstate-per-n-core array has all
>> entries equal to max turbo pstate. So the above three properties
>> are added whenever WOF is supported to ease the reporting of these
>> data in host.
>
> Please add/enhance documentation of the applicable device tree entries
> in doc/device-tree/ibm,opal/power-mgt.rst
>
Okay will do.
>> Signed-off-by: Shilpasri G Bhat <shilpa.bhat at linux.vnet.ibm.com>
>> ---
>> No changes from V5.
>>
>> Changes from V4:
>> - s/prerror/prlog(PR_ERR) which have fwts-annotations
>> - Removed fwts_annotations in macro definitions
>> - Added out-of-bound sanity checks for nominal and turbo pstate
>> - Added size to the "reg" property of /ibm,opal/power-mgt/occ
>>
>> hw/occ.c | 588 +++++++++++++++++++++++++++++++++++++++++++--------------------
>> 1 file changed, 402 insertions(+), 186 deletions(-)
>>
>> diff --git a/hw/occ.c b/hw/occ.c
>> index 9eb32b4..f3b7e7c 100644
>> --- a/hw/occ.c
>> +++ b/hw/occ.c
>> @@ -30,44 +30,137 @@
>>
>> /* OCC Communication Area for PStates */
>>
>> -#define P8_HOMER_SAPPHIRE_DATA_OFFSET 0x1F8000
>> +#define P8_HOMER_OPAL_DATA_OFFSET 0x1F8000
>> +#define P9_HOMER_OPAL_DATA_OFFSET 0x0E2000
>> +#define MAX_PSTATES 256
>> +#define MAX_P8_CORES 12
>> +#define MAX_P9_CORES 24
>>
>> -#define MAX_PSTATES 256
>> -
>> -#define chip_occ_data(chip) \
>> - ((struct occ_pstate_table *)(chip->homer_base + \
>> - P8_HOMER_SAPPHIRE_DATA_OFFSET))
>> -
>> -static bool occ_reset;
>> -static struct lock occ_lock = LOCK_UNLOCKED;
>> -
>> -struct occ_pstate_entry {
>> - s8 id;
>> - u8 flags;
>> - u8 vdd;
>> - u8 vcs;
>> - u32 freq_khz;
>> -} __packed;
>> -
>> -/*
>> - * OCC-OPAL Shared Memory Region Version 2
>> - * https://github.com/open-power/occ/blob/master/src/occ/proc/proc_pstate.h
>> - * Interface defined in 'sapphire_table_t'
>> +/**
>> + * OCC-OPAL Shared Memory Region
>> + *
>> + * Reference document :
>> + *
>> https://github.com/open-power/docs/blob/master/occ/OCC_OpenPwr_FW_Interfaces.pdf
>
> I don't see any 0x90 version info in that document.
>
> Could we also point to the OCC header file?
>
Okay.
>> + *
>> + * Supported layout versions:
>> + * - 0x01 : P8
>> + * - 0x02 : P8
>> + * - 0x90 : P9
>> + * In 0x90 the data is separated into :-
>> + * -- Static Data (struct occ_pstate_table): Data is written once by OCC
>> + * -- Dynamic Data (struct occ_dynamic_data): Data is updated at runtime
>> + *
>> + * struct occ_pstate_table - Pstate table layout
>> + * @valid: Indicates if data is valid
>> + * @version: Layout version
>> + * @v2.throttle: Reason for limiting the max pstate
>> + * @v90.occ_role: OCC role (Master/Slave)
>> + * @v#.pstate_min: Minimum pstate ever allowed
>> + * @v#.pstate_nom: Nominal pstate
>> + * @v#.pstate_turbo: Maximum turbo pstate
>> + * @v#.pstate_ultra_turbo: Maximum ultra turbo pstate and the maximum
>> + * pstate ever allowed
>> + * @v#.pstates: Pstate-id and frequency list from Pmax to Pmin
>> + * @v#.pstates.id: Pstate-id
>> + * @v#.pstates.flags: Pstate-flag(reserved)
>> + * @v2.pstates.vdd: Voltage Identifier
>> + * @v2.pstates.vcs: Voltage Identifier
>> + * @v#.pstates.freq_khz: Frequency in KHz
>> + * @v#.core_max[1..N]: Max pstate with N active cores
>> + * @spare/reserved/pad: Unused data
>> */
>> struct occ_pstate_table {
>> u8 valid;
>> u8 version;
>> - u8 throttle;
>> - s8 pstate_min;
>> - s8 pstate_nom;
>> - s8 pstate_turbo;
>> - s8 pstate_ultra_turbo;
>> - u8 spare;
>> + union __packed {
>> + struct __packed { /* Version 0x01 and 0x02 */
>> + u8 throttle;
>> + s8 pstate_min;
>> + s8 pstate_nom;
>> + s8 pstate_turbo;
>> + s8 pstate_ultra_turbo;
>> + u8 spare;
>> + u64 reserved;
>> + struct __packed {
>> + s8 id;
>> + u8 flags;
>> + u8 vdd;
>> + u8 vcs;
>> + u32 freq_khz;
>> + } pstates[MAX_PSTATES];
>> + s8 core_max[MAX_P8_CORES];
>> + u8 pad[100];
>> + } v2;
>> + struct __packed { /* Version 0x90 */
>> + u8 occ_role;
>> + u8 pstate_min;
>> + u8 pstate_nom;
>> + u8 pstate_turbo;
>> + u8 pstate_ultra_turbo;
>> + u8 spare;
>> + u64 reserved1;
>> + u64 reserved2;
>> + struct __packed {
>> + u8 id;
>> + u8 flags;
>> + u16 reserved;
>> + u32 freq_khz;
>> + } pstates[MAX_PSTATES];
>> + u8 core_max[MAX_P9_CORES];
>> + u8 pad[1024];
>> + } v90;
>> + };
>> +} __packed;
>> +
>> +/**
>> + * OCC-OPAL Shared Memory Interface Dynamic Data Vx90
>> + *
>> + * struct occ_dynamic_data - Contains runtime attributes
>> + * @occ_state: Current state of OCC
>> + * @cpu_throttle: Reason for limiting the max pstate
>> + * @mem_throttle: Reason for throttling memory
>> + * @quick_pwr_drop: Indicates if QPD is asserted
>> + * @pwr_shifting_ratio: Indicates the current percentage of power to
>> + * take away from the CPU vs GPU when shifting
>> + * power to maintain a power cap. Value of 100
>> + * means take all power from CPU.
>> + * @pwr_cap_type: Indicates type of power cap in effect
>> + * @min_pwr_cap: Minimum allowed system power cap in Watts
>> + * @max_pwr_cap: Maximum allowed system power cap in Watts
>> + * @cur_pwr_cap: Current system power cap
>> + * @spare/reserved: Unused data
>> + */
>> +struct occ_dynamic_data {
>> + u8 occ_state;
>> + u8 spare1;
>> + u8 spare2;
>> + u8 spare3;
>> + u8 spare4;
>> + u8 cpu_throttle;
>> + u8 mem_throttle;
>> + u8 quick_pwr_drop;
>> + u8 pwr_shifting_ratio;
>> + u8 pwr_cap_type;
>> + u16 min_pwr_cap;
>> + u16 max_pwr_cap;
>> + u16 cur_pwr_cap;
>> u64 reserved;
>> - struct occ_pstate_entry pstates[MAX_PSTATES];
>> - s8 core_max[16];
>> } __packed;
>>
>> +#define get_homer_opal_data(chip) \
>> + (chip->homer_base + homer_opal_data_offset)
>> +
>> +#define get_occ_pstate_table(chip) \
>> + ((struct occ_pstate_table *)(get_homer_opal_data(chip)))
>> +
>> +#define get_occ_dynamic_data(chip) \
>> + ((struct occ_dynamic_data *)(get_homer_opal_data(chip) + \
>> + sizeof(struct occ_pstate_table)))
>
> I'd prefer these three to be static inline instead.
>
Okay will do.
>> @@ -200,40 +290,119 @@ static bool wait_for_all_occ_init(void)
>> return true;
>> }
>>
>> +#define parse_pstate_limits(pstate_data) \
>> +do { \
>> + pmin = pstate_data.pstate_min; \
>> + pnom = pstate_data.pstate_nom; \
>> + pmax = ultra_turbo_supported ? pstate_data.pstate_ultra_turbo : \
>> + pstate_data.pstate_turbo; \
>> +} while (0)
>
> For clarity of reading the code, I'd prefer just to open code this twice
> rather than hide in a macro that has side-effects.
All the macros defined here which takes "pstate_data" as argument :
parse_pstate_limits(pstate_data)
parse_cpu_pstate_properties(pstate_data)
parse_core_max(pstate_data)
parse_vid(pstate_data)
are the common properties to be parsed at different offsets based on the layout
v(1,2) and v90.
For readability I can perhaps define two functions to parse_v2() and parse_v9()
(and add new functions for every new major version layouts). Then I can squash
all the macros in both the functions. What do you suggest?
>
>> +
>> +/*
>> + * OCC provides pstate table entries in continuous descending order.
>> + * Parse the pstate table to skip pstate_ids that are greater
>> + * than Pmax. If a pstate_id is equal to Pmin then add it to
>> + * the list and break from the loop as this is the last valid
>> + * element in the pstate table.
>> + */
>> +#define parse_cpu_pstate_properties(pstate_data) \
>> +do { \
>> + for (i = 0, j = 0; i < MAX_PSTATES && j < nr_pstates; i++) { \
>> + if (cmp_pstates(pstate_data.pstates[i].id, pmax) > 0) \
>> + continue; \
>> + \
>> + dt_id[j] = pstate_data.pstates[i].id; \
>> + dt_freq[j] = pstate_data.pstates[i].freq_khz / 1000; \
>> + j++; \
>> + if (pstate_data.pstates[i].id == pmin) \
>> + break; \
>> + } \
>> + \
>> + if (j != nr_pstates) { \
>> + prerror("OCC: Expected pstates(%d) is not equal to" \
>> + "parsed pstates(%d)\n", nr_pstates, j); \
>> + goto out_free_vcs; \
>> + } \
>> + \
>> + if (!ultra_turbo_supported) \
>> + break; \
>> + \
>> + if (cmp_pstates(pstate_data.pstate_turbo, pmax) > 0) { \
>> + prlog(PR_WARNING, "OCC: Invalid turbo pstate. Clipping " \
>> + "turbo pstate(%d) to Pmax(%d)\n", \
>> + pstate_data.pstate_turbo, pmax); \
>> + dt_add_property_cells(power_mgt, "ibm,pstate-turbo", \
>> + pmax); \
>> + } else { \
>> + dt_add_property_cells(power_mgt, "ibm,pstate-turbo", \
>> + pstate_data.pstate_turbo); \
>> + dt_add_property_cells(power_mgt, "ibm,pstate-ultra-turbo",\
>> + pstate_data.pstate_ultra_turbo); \
>> + } \
>> +} while (0)
>
> Hrm... soo... I'm not a fan of this as a macro, but I'm unsure of a
> better way to do it... could the macro be PARSE_CPU_PSTATE_PROPERTIES
> (caps) rather than lower case though? parse_cpu_pstate_properties
>
Yup.
>> +
>> +/* core_max[1..n] array provides the max sustainable pstate that can be
>> + * achieved with i active cores in the chip.
>> + */
>> +#define parse_core_max(pstate_data) \
>> +do { \
>> + for (i = 0; i < nr_cores; i++) \
>> + dt_core_max[i] = pstate_data.core_max[i]; \
>> +} while (0)
>
> I'd prefer static inline function to a macro here.
>
>> +
>> +#define parse_vid(pstate_data) \
>> +do { \
>> + for (i = 0, j = 0; i < MAX_PSTATES && j < nr_pstates; i++) { \
>> + if (cmp_pstates(pstate_data.pstates[i].id, pmax) > 0) \
>> + continue; \
>> + \
>> + dt_vdd[j] = pstate_data.pstates[i].vdd; \
>> + dt_vcs[j] = pstate_data.pstates[i].vcs; \
>> + j++; \
>> + \
>> + if (pstate_data.pstates[i].id == pmin) \
>> + break; \
>> + } \
>> +} while (0)
>
> I'd prefer this code inline rather than hiding in macro - or in its own function.
>
>> +
>> +#define allocate(ptr, size, fail_label) \
>> +do { \
>> + ptr = malloc((size)); \
>> + if (!ptr) { \
>> + prerror("OCC:" #ptr " array alloc failure\n"); \
>> + goto fail_label; \
>> + } \
>> +} while (0)
>
> Just use malloc() and assert() on failure. Since this is at boot time,
> that's okay.
>
Okay will do.
>> +
>> /* Add device tree properties to describe pstates states */
>> -/* Retrun nominal pstate to set in each core */
>> -static bool add_cpu_pstate_properties(s8 *pstate_nom)
>> +/* Return nominal pstate to set in each core */
>> +static bool add_cpu_pstate_properties(int *pstate_nom)
>> {
>> struct proc_chip *chip;
>> uint64_t occ_data_area;
>> struct occ_pstate_table *occ_data;
>> struct dt_node *power_mgt;
>> - u8 nr_pstates, nr_cores = 0;
>> - s8 pmax;
>> - /* Arrays for device tree */
>> - u32 *dt_id, *dt_freq;
>> - u8 *dt_vdd, *dt_vcs;
>> - s8 *dt_core_max = NULL;
>> - bool rc, ultra_turbo_en;
>> + u32 *dt_id, *dt_freq, *dt_core_max = NULL;
>> + int pmax, pmin, pnom;
>> + u8 *dt_vdd = NULL, *dt_vcs = NULL, nr_pstates, max_cores;
>> + bool ultra_turbo_supported, rc = false;
>> int i, j;
>>
>> prlog(PR_DEBUG, "OCC: CPU pstate state device tree init\n");
>>
>> - /* Find first chip and core */
>> + /* Find first chip */
>> chip = next_chip(NULL);
>>
>> /* Extract PState information from OCC */
>> + occ_data = get_occ_pstate_table(chip);
>>
>> - /* Dump state table */
>> - occ_data_area = chip->homer_base + P8_HOMER_SAPPHIRE_DATA_OFFSET;
>> -
>> + /* Dump first 16 bytes of PState table */
>> + occ_data_area = (uint64_t)occ_data;
>> prlog(PR_DEBUG, "OCC: Data (%16llx) = %16llx %16llx\n",
>> occ_data_area,
>> *(uint64_t *)occ_data_area,
>> *(uint64_t *)(occ_data_area+8));
>>
>
> may as well remove the trailing whitespace here while you're at it.
>
>
Sure thanks will do.
Regards,
Shilpa
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